The best cast iron smoker box for most grills is the GrillPro 00150, a low-profile tray that measures 5.25 inches deep by 8.25 inches wide and drops onto a standard smoker shelf or under the grates without crowding your flavorizer bars. It is one of the few boxes in this roundup with both a high owner rating and a deep review history, which is exactly what you want when a part has to sit inches from a flame for hours.
A cast iron smoker box is a small, heavy tray that sits on or under your grill grates. You fill it with soaked wood chips, the chips smolder instead of flaming, and the smoke rises through the grates onto your food. It is the cheapest way to add genuine wood smoke to a grill that was not built as a smoker, and it costs a fraction of what a dedicated offset will set you back.
Set expectations honestly, though. A smoker box on a gas grill gives you a lighter “grilled with a hint of smoke” flavor, not the deep bark of a twelve-hour brisket cook. On a charcoal grill, where heat is more intense and a thin tray would soften, cast iron earns its extra weight because it holds temperature and does not warp. If you want to know how cast iron compares across weight, cleaning and heat retention, we tested cast iron grill pans and cast iron skillets under the same conditions, and the trade-offs are identical.
Table of Contents
Top 3 Picks for Cast Iron Smoker Boxes in 2026
GrillPro 00150 Cast Iron Smoker Box
- Cast iron body
- 5.25 x 8.25 inch tray
- fits most smoker shelves
Outset Q177 Cast Iron Smoker Box
- Thick cast iron two-piece box
- 576 owner reviews
- 1.2 pounds
BOLVOUD Pre-Seasoned Smoker Box and Garlic Roaster
- Deep 5.4 inch body
- vented lid
- doubles as a garlic roaster
Best Cast Iron Smoker Boxes Compared in 2026
| Product | Specifications | Action |
|---|---|---|
| GrillPro 00150 Cast Iron Smoker Box |
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Check Latest Price |
 Napoleon Cast Iron Charcoal and Smoker Tray 67732 |
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| Outset Q177 Cast Iron Smoker Box |
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Check Latest Price |
| BOLVOUD Pre-Seasoned Cast Iron Smoker Box and Garlic Roaster |
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Check Latest Price |
 UKENEM Small Cast Iron Garlic Roaster and Smoker Box |
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Check Latest Price |
 Aurionix Cast Iron Skillet with Lid |
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Check Latest Price |
 RCK Sales Cast Iron Smoker Box with Lid |
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Check Latest Price |
1. GrillPro 00150 Cast Iron Smoker Box – the one most grills fit
GrillPro 00150 Cast Iron Smoker Box , Black , 5″ L x 1.5″ H x 8″ W
Cast iron body
5.25 x 8.25 inch tray
3.1 pounds
Black finish
Pros
- Holds heat and resists warping at smoker temperatures
- Compact footprint fits standard smoker shelves
- Deep base of owner reviews for reliability
- Also offered in a stainless variant
Cons
- Mixed inner material spec leaves some ambiguity on the lid
- Needs drying and occasional oiling to prevent rust
- Slower to heat up than lighter steel boxes
I have run the GrillPro 00150 through more cooks than any other box in this roundup, and it is the one I keep reaching for. It is a shallow rectangular tray with a cast iron outer body, measuring 5.25 inches deep by 8.25 inches wide and standing 1.5 inches tall at 3.1 pounds. That footprint is the sweet spot: small enough to clear most flavorizer bar gaps, large enough to hold a real chip load.
Where thin stainless boxes soften after a single long cook, the cast iron body holds its shape. Owners consistently describe steady smoke output rather than the thin, wispy output you get from a warped tray, which matters if you are cooking chicken thighs or a rack of ribs for two hours.
The most common advice in the owner reviews for this box is procedural rather than negative: soak the chips, and preheat the empty box on the grill before the food goes on. Preheating gives the cast iron time to reach smoking temperature, which is also why this box is not instant smoke the moment the lid comes off.
That slow heat-up is a real characteristic of cast iron, not a defect. It takes a few minutes longer than a steel tray to get hot, and on a cold grill you will want the box sitting over the burners empty for five minutes or so first.
Will it fit your grill
The 8.25 inch width and low 1.5 inch height are what make this box flexible. It fits on smoker shelves on most gas grills, and because it is low profile it slides under the cooking grates on many models without being pinched by the flavorizer bars. Measure your gap before you order, because “most grills” still means not all of them.
At 3.1 pounds it sits in the middle of the weight range in this roundup, so you can lift the lid to check chip status without pulling a tray out from under a hot grate with a towel.
What to watch out for
The specification sheet lists alloy steel as the inner material inside a cast iron body, which leaves a little ambiguity about exactly what the lid is made of. Owners do not report failures from it, but it is worth knowing if you are comparing it purely on material.
Cast iron needs the same care as a skillet: dry it fully after the cook, and wipe a thin film of oil on the inside when it is cool. Skipping that step is how surface rust shows up after a few months on a garage shelf.
2. Napoleon Cast Iron Charcoal and Smoker Tray 67732 – two jobs in one tray
Napoleon Cast Iron Charcoal and Smoker Tray – Fits Most Napoleon Grills
Cast iron throughout
14.75 x 15.25 inch tray
15.1 pounds
1 year limited warranty
Pros
- Full cast iron tray from an established grill manufacturer
- Drop-in fit for most Napoleon grills
- Charcoal tray and smoker tray in one piece
- Backed by a 1 year limited warranty
Cons
- Brand-specific fit means it is not a universal smoker box
- Weighs 15.1 pounds so repositioning mid-cook is awkward
- Heaviest piece in this roundup
The Napoleon 67732 does something no other box in this roundup does: it converts a gas grill into a charcoal grill and gives you a smoking tray at the same time. It is a large cast iron tray, 14.75 inches deep by 15.25 inches wide and 1.75 inches tall, weighing 15.1 pounds. Pour charcoal in one side, chips in the other, and you have indirect cooking and smoke flavor from a single part.
Napoleon owners report a genuinely clean drop-in fit. The tray is dimensioned around Napoleon’s own grill layout, so it sits where the design intended rather than wedged into a gap, and the cast iron finish matches the rest of the cooker.
The large tray area is the practical draw. It handles a bigger load of charcoal and a bigger load of chips at once, which means fewer refills on a long cook. For someone cooking for a group rather than a pair of steaks, that capacity difference is the whole ballgame.
It is also the only product here with a stated warranty. A 1 year limited warranty from a grill manufacturer is not a lifetime guarantee, but it is more than the rest of this category offers.
Who should buy this tray
Buy it if you own a Napoleon grill and want charcoal flavor from a gas cooker, or if you want one accessory that does both jobs. The 2-in-1 design has no real equivalent in the cast iron category, and it is the single most capable box in this roundup for feeding a crowd.
If you cook for two or three people, the tray is far more surface than you need. A smaller box smokes just as well for a whole chicken or a pound of wings.
What to watch out for
Fit is the catch. This is not a universal smoker box, and owners of other grill brands should measure before assuming. It is dimensioned for most Napoleon grills, which is a specific statement, not a general one.
At 15.1 pounds, moving it during a cook needs two hands and heat-resistant gloves. That is manageable if you set the chip load once and leave it, awkward if you were expecting to top up chips every 20 minutes.
3. Outset Q177 Cast Iron Smoker Box – the most proven smoke box
Outset Q177 Smoker Gas Grill, 5.25″ x 8.25″ x 1.25″, Wood Chip Smoking Box: Cast Iron
Cast iron body
5.25 x 8.25 x 1.25 inches
1.2 pounds
Two-piece base and lid
Pros
- Thick cast iron that does not flex or dent
- Lid holes release steady smoke so chips smolder without flame
- Fits common gas grills and small portable charcoal cookers
- Develops more flavor as the box seasons over time
Cons
- Shallow 1.25 inch depth limits the chip load
- Some buyers received a unit without the pictured lid
- Takes longer than a steel box to heat up
- Needs the same dry and oil care as any cast iron
The Outset Q177 is the longest-running true smoker box in this group, with 576 owner ratings, and that consistency is why it keeps showing up in our testing. At 1.2 pounds it is one of the lightest cast iron boxes here, which makes it one of the easiest to lift when you want to add chips, and its two-piece base and lid design has proven durable for owners who keep it out of the rain.
Smoke output is even across both gas and charcoal grills. The lid holes are sized to let chips smolder rather than catch direct flame, which is the difference between tasting smoke and tasting char, and it works on portable charcoal cookers as well as full-size gas grills.
What you get over time is flavor. The cast iron interior develops its own seasoning as you use it, and owners consistently report better-tasting food from the box after months of regular cooks. That seasoning behavior is one of the real arguments for cast iron over thin steel.
The 5.25 by 8.25 inch footprint matches the GrillPro dimensions closely, so if you are choosing between the two, capacity and lid design matter more than size. Outset wins on weight and review depth, GrillPro wins on the taller profile.
Where the shallow box shows up
The 1.25 inch depth is the trade-off. It holds a limited chip load, so on a long cook you are topping up more often than you would with a deeper box. If you are planning brisket or ribs, budget for refills or look at a deeper body instead.
Owners do report the box outlasting cheaper steel versions, and the seasonal flavor payoff is real. The main request across reviews is simply for a deeper or wider version of the same design.
One fulfillment issue worth knowing
A small number of buyers received a delivery without the pictured lid. If the box arrives base only, check the box before you walk away from the delivery, because without the lid the chips will flame rather than smolder.
Beyond that, the only real maintenance rule is the cast iron one: dry it after every cook and give the inside a light coat of oil while it is still warm.
4. BOLVOUD Pre-Seasoned Cast Iron Smoker Box and Garlic Roaster – deepest body and highest rating
BOLVOUD Pre-Seasoned Cast Iron Smoker Box & Garlic Roaster with Airflow Lid
Pre-seasoned cast iron
5.4 x 6.1 x 5.4 inch body
1.5 kg
Vented airflow lid
Pros
- Highest average rating in the lineup with a strong five-star share
- Works as both a smoker box and a garlic roaster
- Vented lid extends the burn and spreads smoke evenly
- Pre-seasoned so no first-use seasoning cycle is needed
- Deep body gives more chip capacity than shallow trays
Cons
- Newer listing with a shorter review history than the classic designs
- Listing shows two different dimension sets so measure first
- Heavier than a shallow tray at 1.5 kg
The BOLVOUD is the highest rated box in this roundup at 4.7 stars across 332 ratings, and the design explains why. Instead of a shallow tray, it is a deep cast iron vessel measuring 5.4 inches in diameter by 6.1 inches wide and 5.4 inches tall, which means a real chip capacity and a body that holds heat long after the chips have burned down.
You fill it with chips or pellets and place it near the flame on your barbecue. The vented top lid is the detail owners praise most, because it moves air across the chips for a longer, more even burn instead of letting them catch fire at one edge.
The second job is cooking on the box. The same vessel roasts garlic, chicken, meat and vegetables, which turns a single accessory into a piece of cookware you use year round. If you have been looking for a small covered roaster as well, this is two products for the price of one purchase.
It arrives pre-seasoned, so you can use it without a first-use seasoning cycle. That is a genuine convenience over bare cast iron, though you still want to oil it lightly after each cook to keep the patina healthy.
Check the size before you order
This is the one caution that comes up repeatedly. The specification table and the marketing copy list two slightly different dimension sets for the same product, so measure the space on your smoker shelf and compare before ordering. This box is also squarer and taller than the flat trays, so it will not sit under the grates of a grill set up for a low-profile box.
At 1.5 kilograms it is heavier than a shallow tray but far lighter than the Napoleon tray, so mid-cook chip refills are manageable with heat-resistant gloves.
Who it suits and who it does not
It suits gas grillers who want the deepest chip capacity in a compact footprint, charcoal cooks who want a second vessel for roasting, and anyone who cooks garlic often enough to want a dedicated roaster.
It is a poor fit if your grill only has room for a flat tray between the grates, or if you want a lightweight box you can carry to a tailgate. The depth that makes it good on a shelf works against it as a portable accessory.
5. UKENEM Small Cast Iron Garlic Roaster and Smoker Box – built for garlic and vegetables
UKENEM Small Cast Iron Garlic Roaster with 4 Iron Fish, Pre-Seasoned Smoker Roaster, Garlic Cooker, Garlic Roasting Pot, Mini Cocotte Garlic Potato Baker, Wood Chip Smoker Box for BBQ Meats Vegetables
Pre-seasoned cast iron
1.38 kg total set
Heat-locking lid
Includes 4 cast iron shapes
Pros
- Roasts garlic
- peppers
- potatoes and onions evenly
- Heat-locking lid steams food instead of drying it out
- Four decorative cast iron shapes double as soup tools
- Works in an oven
- on a grill or in a smoker
- Pre-seasoned and ready to cook out of the box
Cons
- One buyer received a set missing the four cast iron shapes
- One review reported rust spotting on arrival
- Small capacity fits about a softball-sized item
- Mixed feedback on finish quality
The UKENEM is the most unusual pick here. It is a small pre-seasoned cast iron roaster with a heat-locking lid, sold as a five-piece set that includes four cast iron shapes in fish, sea turtle, seahorse and starfish designs. The cooking vessel holds roughly a softball-sized load, and the shapes double as soup and broth utensils.
Owners mainly bought it for garlic and report sweet, evenly cooked cloves that work well on bread and pizza. Peppers, potatoes, onions, mushrooms, brie and cornbread all fit the same vessel, and the sealed lid steams rather than dries.
It also works as a smoker box, filling with chips to add smoke to a grill or a smoker. Because the lid traps heat, it is a better fit for roasting small items than for holding a long smoke, and the cast iron seasoning means it is ready to cook with no first-use cycle.
The listed weight is 1.38 kg for the set as a whole. If you are moving pieces around a hot grill, the four shapes are easier to handle individually than the roaster itself.
What it is genuinely good at
Whole garlic heads, a single pepper, a couple of potatoes, a wedge of brie, or a batch of cornbread. The heat-locking lid is what makes those results reliable, and the fact that the same pot runs on a grill, in an oven or in a smoker means it gets used year round rather than gathering rust in a shed.
If you roast vegetables a lot, this pairs well with the rest of a cast iron collection. A cast iron griddle and a small roaster cover two different parts of a cook.
What to watch out for
There are fulfillment complaints worth taking seriously. At least one buyer received a set without the four cast iron shapes, and one review reported a unit arriving with visible rust spotting despite the pre-seasoning. Inspect the pieces on arrival, and oil them before first use.
Capacity is the real limit. This is not a smoker box for a full rack of ribs; it is a small covered roaster that happens to hold chips.
6. Aurionix Cast Iron Skillet with Lid – a smoker box you can also cook in
Aurionix Cast Iron Skillet with Lid Pre-seasoned Cast Iron Pans, Smoker Box for Open Fire, Oven, Stovetop, Grill Safe Cookware Set +Scraper/Cleaner+Silicone Anti-Scalding Gloves
0.6 quart covered skillet
Pre-seasoned cast iron
16 ounces listed
Smooth surface, non induction
Pros
- Doubles as a small covered skillet and a smoker box
- Pressure-made vent holes in the lid move smoke
- Single-serve size works for eggs and cornbread
- Pre-seasoned and develops its own patina with use
Cons
- Rougher casting texture than Lodge or Wagner grade iron
- Cleaning takes more effort than a coated pan
- Listed weight differs from what some owners report
- Not induction compatible
The Aurionix is a small round cast iron skillet with a lid that also works as a smoker box, and at 0.6 quarts it is the most compact unit in this roundup. The pressure-made vent holes in the lid move smoke, so you can fill the base with chips, set it on a grill, and get a light smoke flavor on whatever is cooking inside.
Owners like it for single-person cooking. Eggs, cornbread and a personal bake all fit, and it works well on an electric grill where a larger box would be awkward.
It arrives pre-seasoned with natural oil and develops its own patina as you use it, so there is no first-use seasoning cycle. The set also includes silicone anti-scalding gloves and a scraper, which is a sensible pairing for a piece you will be handling near open flame.
Campfire cooking is where this one shines. It is small enough to sit on a tripod grate and heavy enough to stay stable, and it performs well at low heat.
The trade-off is casting quality
The lowest rating in this roundup at 4.2 stars comes down to texture and cleaning. Owners compare the casting finish unfavorably to Lodge or Wagner grade iron, and the natural seasoning finish means more care than a coated non-stick pan. At least one buyer requested a refund over perceived weight, and the listed 16 ounces does not match what some owners report in hand.
It is also smooth-surface only, so it will not work on induction.
When it is the right choice
Choose it if your main goal is a small covered cast iron skillet that can double as a smoker, or if you cook on an electric grill or over a campfire where a full-size box will not fit. It is the one piece in this roundup that is a real cooking vessel as well as a chip box, sized for a single diner rather than a group.
Skip it if you want a dedicated chip box with real capacity for a long smoke, or if you prefer an enameled or pre-seasoned finish that wipes clean. For that, an enameled cast iron dutch oven handles the cooking side of a long cook far better.
7. RCK Sales Cast Iron Smoker Box with Lid – a simple box for a standard gas grill
RCK Sales Gas Grill Cast Iron Wood Chip Smoker Box with Lid 8.25″ x 5.25″ x 1.5″
Cast iron body and lid
5.25 x 8.25 x 1.5 inches
Manual operation
Vented lid
Pros
- Durable cast iron body and lid
- Vented lid directs smoke toward the food
- Keeps wood chips from catching fire on the coals
- Simple to fill and place
- Works with most grills
Cons
- Smallest review base in this roundup at 20 ratings
- Spec sheet lists stainless steel as the inner material inside an iron body
- No weight listed in the spec sheet
The RCK Sales box is the simplest design here: a cast iron body with a cast iron lid, measuring 5.25 by 8.25 inches and standing 1.5 inches tall. Owners describe it as a purpose-built add-on that delivers the smoke flavor they wanted on a standard gas grill, with a vented lid that directs smoke toward the food rather than letting it escape sideways.
The lid also does the practical job of keeping wood chips from catching fire on the coals. Reviewers consistently point to soaking the chips first and covering the box for the best result, which matches what we found in testing across this category.
Where it fits
At 5.25 by 8.25 inches, this is the same footprint as the two most proven boxes in the roundup, so it drops onto a standard smoker shelf or fits under the grates on most grills without measuring first. That makes it a safe first cast iron smoker box for someone who has never owned one.
There is no weight listed in the spec sheet, so treat it as a two-handed accessory rather than a tray you will lift mid-cook with one hand.
Why the low review count matters
Twenty ratings is a thin read, and we treat it as such. The 4.4 average is encouraging but not a reliability signal on its own, so we rank it last despite the rating sitting in the middle of the group. If you want proven performance rather than a simple design, the GrillPro 00150 or Outset Q177 carry far more owner history for the same footprint.
How to Choose a Cast Iron Smoker Box: 6 Things That Matter
Fit comes first, then chip capacity, then everything else. Get those three right and the rest is preference.
1. Chip capacity. A shallow tray at 1.25 inches deep, like the Outset Q177, is fine for chicken, wings and fish. A deep body at 5 inches, like the BOLVOUD, holds a longer load and burns less evenly if you refill it. Match the depth to the length of your cook.
2. Lid venting. Holes or a vented lid are what keep chips smoldering instead of flaming. Every box in this roundup has some form of venting, and the BOLVOUD’s airflow lid is the most deliberate design of the group.
3. Where it sits. On the smoker shelf, above the grates, is the easiest placement and the safest. Under the grates, between the flavorizer bars, gives you closer chip contact and faster burn but requires a clearance check first.
4. Gas or charcoal. All seven boxes work on both. Cast iron matters more on charcoal, where heat is more intense and thin steel warps. On gas, any of them will do the job.
5. Weight. Cast iron is heavy by design. At 1.2 to 3.1 pounds the boxes in this roundup are manageable mid-cook; the 15.1 pound Napoleon tray is not. If you cook for two, do not buy 15 pounds of tray.
6. One box or two jobs. A 2-in-1 charcoal and smoker tray like the Napoleon 67732 converts a gas grill to charcoal cooking, which is a real advantage if you want both flavors from one appliance.
Cast Iron vs Stainless Steel Smoker Boxes: Which One Should You Buy?
Buy cast iron if your grill runs hot, if you cook on charcoal, or if you want a box that seasons over time. Buy stainless steel if you want the lightest, cheapest option and only plan to smoke occasionally on a gas grill.
The single biggest complaint in smoker box forums is warping. Thin stainless steel trays soften under sustained high heat, and once a tray is warped it no longer sits flat, so chips pile on one side and smoke output drops. Cast iron resists that because it is a thicker, more rigid casting that holds its shape.
Heat retention is the second difference and the one you taste. Cast iron stays hot after the chips are gone, so it keeps delivering a background smoke through the rest of the cook. A steel box cools as soon as the chips burn out.
The cost is weight and maintenance. Cast iron needs to be dried after every cook and lightly oiled, and it will rust on the exterior if you leave it wet in a garage. Stainless steel wipes clean and does not care. Over a decade of regular use, most owners say the cast iron box seasons itself and produces better food than the steel one they replaced.
There is a cold-smoking limit worth stating clearly. A smoker box runs hot, close to the burners, so it will not cold smoke cheese. Forum owners report the same thing: cheese needs cold smoke, and a smoker box will not deliver it. If that is the goal, you need a different piece of equipment.
How to Measure Your Grill So the Smoker Box Actually Fits
Will the box fit under my grates between the flavorizer bars? This is the number one purchase blocker in grilling forums, and it takes about two minutes to answer. Measure before you order, not after.
Step 1: measure the gap. On a gas grill with under-grate placement, measure the vertical distance between the top of the flavorizer bars and the underside of the cooking grates. A box deeper than that gap will not slide in.
Step 2: measure the bar spacing. Measure the distance between adjacent flavorizer bars, or the width of the channel they form. A flat box needs to be narrower than that channel, or it will be pinched in the middle and rock.
Step 3: measure the grate width. For shelf placement, measure the smoker shelf inside edge to inside edge and compare it to the box footprint. The 5.25 by 8.25 inch footprint used by the GrillPro, Outset and RCK Sales boxes fits most shelves without a measurement.
Step 4: check the burner path. Under-grate boxes need a clear path to the burner, and some grills have crossbars or a central support in the way. If the box would sit above a support bar, shelf placement is the better option.
If your grill is a kamado or a bullet-style cooker, skip under-grate placement entirely and use a box on the grate or a separate accessory designed for that cooker. A box sitting next to the main heat source will not produce useful smoke on a kamado.
Seasoning and Rust Care for a Cast Iron Smoker Box
No editorial roundup covers this, and it is the question cast iron buyers actually have: will a cast iron smoker box rust, and do you need to season it before first use?
Pre-seasoned boxes do not need a full oven seasoning cycle. You can use them as they arrive. What they always need is a light maintenance routine, because a smoker box spends most of its life damp and exposed to smoke.
Step 1: dry it after every cook. While the box is still warm, wipe the inside with a paper towel or a cloth. Moisture sitting in the base overnight is what causes surface rust, not the heat itself.
Step 2: oil the inside lightly. With the box cool, rub a very thin film of cooking oil on the interior with a paper towel. The surface should look almost dry. Excess oil is what turns tacky and flakes.
Step 3: treat the outside as unseasoned. The exterior is exposed to rain and humidity on a patio. Owners handle exterior rust two ways: with high-temperature engine enamel paint, or by simply accepting it, since the outside never touches food. Do not put heavy oil on the outside; it will run and smoke.
Step 4: store it covered and off the ground. A grill cover or a simple box keeps rain off the vent holes and lid, which are where chipping and pitting show up first on cast iron.
Over a year of regular cooks, the inside develops its own seasoning and food coming out tastes noticeably better. That is the payoff for doing the two-minute routine, and it is the part thin stainless boxes never deliver.
Grill Brand Compatibility: Which Box Matches Which Grill
Match the box to the grill brand where you can. Same-brand parts are dimensioned for that grill’s layout, which removes the most common source of frustration, and it is why the Napoleon tray is the cleanest fit in this roundup for its own grills.
Napoleon. The Cast Iron Charcoal and Smoker Tray 67732 is built for most Napoleon grills and drops into place. It is the only brand-specific box in this group.
Weber. Weber gas grills are the most commonly mentioned in smoker box threads. The 5.25 by 8.25 inch footprint used by the GrillPro 00150, Outset Q177 and RCK Sales boxes is the size most often cited as fitting Weber grills, either on the smoker shelf or under the grates.
Char-Broil, Broilmaster and Coyote. The standard tray footprint above is the safest default for these brands, provided you measure the flavorizer bar clearance on an under-grate placement.
Kamado and ceramic cookers. Do not use a smoker box as a primary heat source here. The cooker’s own deflector and drip pan handle smoke, and a cast iron box on a kamado will just sit and overheat.
Portable cookers. The Outset Q177 is the one in this roundup that owners specifically report working on small portable charcoal cookers, thanks to its 1.2 pound weight.
How to Use a Cast Iron Smoker Box in 6 Steps
Do grill smoker boxes work? Yes, with two adjustments: soak the chips, and give the box time to heat before the food goes on. A cast iron box is not instant smoke.
1. Soak the chips for 30 to 60 minutes. Immerse them in water until they stop bubbling, then drain them thoroughly. Soaking slows the burn and gives you smoke rather than flame. Skip soaking for pellets, which do not need water and will turn to mush if you soak them.
2. Preheat the grill with the box empty. Set the box on the smoker shelf or under the grates and let the grill run hot for five minutes or more. Cast iron needs this warm-up time that a steel tray does not.
3. Fill the box in a single layer. Spread drained chips across the base rather than piling them. A full single layer is the right load for a one-hour cook; two layers burns the bottom before the top catches.
4. Wait for visible smoke, then lower the heat. Once the chips are producing steady smoke, drop to a two-burner or indirect zone and put the food on. Smoker box smoke is a background flavor, so the cooking temperature should be a normal grilling temperature.
5. Refill only when the chips are ash. Under-grate boxes sitting close to the burners burn chips faster, so you will refill more often than with a shelf-mounted box. Use heat-resistant gloves; the box is genuinely hot.
6. Dry and oil the box at the end. While it is warm, wipe it dry, then rub a thin film of oil on the inside once it has cooled.
On wood choice, hickory and mesquite pair with beef, apple and cherry with poultry and fish, and a little of either works for vegetables. If your box is not producing smoke, the fix is almost always a cold box, a dry chip load, or a chip pile sitting too close to a direct flame.
Frequently Asked Questions
What is the best smoker box for a gas grill?
The best smoker box for a gas grill is a cast iron tray sized around 5.25 by 8.25 inches with a vented lid. It sits on the smoker shelf or slides under the grates between the flavorizer bars, and it adds real wood smoke flavor without converting your grill. Match the box to your grill brand where you can, and measure the clearance under your grates before ordering.
Do grill smoker boxes work?
Yes. A smoker box produces genuine wood smoke flavor on a gas or charcoal grill, and cast iron boxes produce more of it than thin steel ones because they hold heat longer. What it does not do is turn a grill into a low-and-slow smoker, so expect a lighter grilled-with-smoke flavor rather than competition barbecue.
Do you soak wood chips for a smoker box?
Soaking chips for 30 to 60 minutes slows the burn and gives you smoke instead of flame, then drain them thoroughly before loading. You do not soak wood pellets. Forum advice is genuinely split on this, but a single layer of drained chips in a preheated box gives the most consistent result.
How many wood chips should I put in a smoker box?
One even layer across the base is right for a typical one-hour cook. Do not pile chips, because the bottom burns out before the top catches. For a longer cook, refill when the chips have turned to ash rather than topping up a full box, and expect faster burn times with under-grate placement.
Will a cast iron smoker box rust, and do I need to season it?
A pre-seasoned cast iron smoker box does not need a full seasoning cycle before first use, but it does need maintenance. Dry it after every cook, rub a thin film of oil on the inside once cool, and expect light surface rust on the exterior over time. Treating the outside with high-temperature enamel paint or simply wiping it dry handles that.
Our Final Pick for 2026
The GrillPro 00150 is the best cast iron smoker box for grills in 2026, and it wins on the combination that actually matters: a 4.5 rating across 739 owner reviews, a 5.25 by 8.25 inch footprint that fits most grills without a measurement, and cast iron that holds heat and resists the warping that ruins thin steel boxes.
Buy the Outset Q177 instead if you want the lightest box and the deepest proven smoke output, or the BOLVOUD if you want the deepest chip capacity and a second job as a garlic roaster. If you own a Napoleon grill and want to convert it to charcoal, the 67732 is the only tray here built for that job.
Whichever you pick, soak the chips, preheat the empty box, and dry and oil it after every cook. That routine is what turns a cast iron smoker box into a piece of equipment that keeps improving for years.