Buying guide
How to choose a patio heater
Six questions, in this order. Answer them and the shortlist is usually one or two products, which is a far better outcome than a list of twenty.
Ask them in this order: is there a roof, are the sides enclosed, how many square feet, how exposed is it, is there an outdoor circuit, and what is the budget. The first two eliminate whole categories, the third sizes it, and the last three narrow to a model.
1. Is there a roof over it?
This is the highest-leverage question and it takes a second. A roof retains warmed air, which cuts the heat you need by roughly a third on our sizing model, and it gives you something to mount a radiant heater to. It also introduces a clearance requirement that most towers cannot meet.
Roof: go electric, mounted. No roof: propane is on the table and probably the answer. The covered patio page has the clearance arithmetic if you have a roof and want to be sure.
2. Are the sides enclosed?
Screens, panels, walls, zip-down covers. If air does not move freely through the space, combustion heaters are out — not marginal, out. A propane heater consumes oxygen and produces flue gas, and every manual restricts it to outdoor use.
This question catches people who did the first one correctly. A screened porch has a roof and looks like a covered patio, and the correct heater for it is a much shorter list. The screened porch page.
3. How many square feet?
Measure it. Length times width, and be honest about the part you actually sit in rather than the whole slab. Then put it into the calculator, which applies the enclosure and exposure factors and shows every step.
Work out your patio
How much heater does this patio need?
The answer
3,360 BTU/h
for 168 sq ft. That is 985 watts if you go electric, which one standard outlet can deliver.
The working
- 12 ft x 14 ft = 168 sq ft
- 168 sq ft x 20 BTU/sq ft = 3,360 BTU/h for an open patio in still air
- x 1 for “Open sky, no roof” = 3,360 BTU/h
- x 1 for average — some exposure = 3,360 BTU/h
Propane, per hour
$0.10
Electric, per hour
$0.18
20 lb cylinder lasts
128.3 h
The threshold worth remembering: about 5,100 BTU/h is what a single 1,500 W electric unit produces. If the calculator returns less than that, electric will do it. Much more, and you are looking at propane or at two electric units on two circuits.
4. How exposed is it?
This is the question people skip and then regret. A patio with a wall on two sides behaves completely differently from one on an open corner lot. On our model the difference is a factor of 1.4 versus 0.9 — about 55 percent more heat required for the exposed case.
If the honest answer is exposed, the highest-value purchase is probably not a heater at all. A windbreak reduces the requirement by more than any upgrade within the heater category does, and costs less.
5. Is there an outdoor circuit?
For any electric option: you need an outdoor-rated, GFCI-protected outlet, and a 1,500 W continuous load wants that circuit largely to itself. An extension cord run out through a window is not an answer for a 12.5-amp continuous appliance.
If there is no circuit and adding one is a real job, that is a legitimate reason to choose propane even under a roof — provided the clearance works. It is a trade between an electrician and a clearance measurement, and both are worth checking before buying.
6. What is the budget, including the running cost?
The purchase price is the smaller half of this for anyone who uses a heater regularly. Four hours a night for a month costs about $33 on a 1,500 W electric unit and about $168 on a 48,000 BTU propane tower at published average prices. Over a season those are not similar numbers.
Electric, per hour
| Rated power | Per hour | 4-hour evening | Per month, 4 h a night |
|---|---|---|---|
| 750 W | $0.14 | $0.55 | $16.51 |
| 900 W | $0.17 | $0.66 | $19.81 |
| 1,200 W | $0.22 | $0.88 | $26.41 |
| 1,500 W | $0.28 | $1.10 | $33.01 |
| 2,000 W | $0.37 | $1.47 | $44.02 |
| 3,000 W | $0.55 | $2.20 | $66.02 |
At 18.34 cents per kWh (June 2026 U.S. residential average). Substitute your own rate: it is on your bill, and the arithmetic is watts ÷ 1000 x hours x rate.
Propane, per hour
| Rated input | Per hour | 4-hour evening | Per month, 4 h a night |
|---|---|---|---|
| 11,000 BTU/h | $0.32 | $1.29 | $38.61 |
| 40,000 BTU/h | $1.17 | $4.68 | $140.40 |
| 46,000 BTU/h | $1.35 | $5.38 | $161.46 |
| 48,000 BTU/h | $1.40 | $5.62 | $168.48 |
| 50,000 BTU/h | $1.46 | $5.85 | $175.50 |
At $2.674 per gallon (week ending March 30, 2026 U.S. residential average) and 91,420 BTU per gallon. Exchange-cage cylinders cost materially more per gallon than a bulk refill, so treat this as the floor.
Quick picks
Ranked for fit, not for hype. Output is the maker’s published figure; reach is computed from it or from the maker’s own radius claim, and the table says which. Tap a row for the full write-up, or go straight to the listing.
| # | Product | Best for | Output | Reach | Price |
|---|---|---|---|---|---|
| 1 | Amazon BasicsNo photo Amazon Basics 46kOne of the very few towers whose maker publishes a coverage radius rather than a vague area, and the 9 ft figure survives the arithmetic. That alone puts it ahead of most of the field. | The published-radius honesty test | 46,000 BTU | 254 sq ft claimed | Check price on Amazon |
| 2 | Dr. Infrared HeaterNo photo Dr Infrared 1500 WRadiant heat that a breeze cannot blow out, on a plug. 1,500 W is only 5,118 BTU/h, which sounds like nothing next to a propane tower and lands far more of itself on you. | Wind, and anywhere with a roof | 1,500 W | 256 sq ft | Check price on Amazon |
| 3 | AZ Patio HeatersNo photo Hiland tabletop11,000 BTU heats a table, not a patio, and being clear about that is the whole point. For a bistro table on a balcony it is the right size and nothing bigger fits. | One table, four people | 11,000 BTU | 550 sq ft | Check price on Amazon |
Reach marked “claimed” is the maker’s own published figure. Reach without that label is ours, computed from published output at 20 BTU per square foot for an open patio. Neither is a measurement we took.
Top pick · The published-radius honesty test
Amazon Basics 46,000 BTU Outdoor Propane Patio Heater
One of the very few towers whose maker publishes a coverage radius rather than a vague area, and the 9 ft figure survives the arithmetic. That alone puts it ahead of most of the field.
- Fuel
- Propane
- Output
- 46,000 BTU/h
- Reach (claimed)
- 254 sq ft · 9.0 ft radius
- Cost per hour
- $1.35
What works
- A published 9 ft radius is a 254 sq ft circle, and 46,000 BTU is far more than that area needs — a claim on the conservative side of its own specification, which is rare here
- The water-fill base box is a real anti-tip measure, not a sticker: filled, it is the difference between a windy evening and a repair bill
- One-touch ignition and a chain for the cylinder are both small things the cheap clones drop
What does not
- The listing does not name a safety certifying body, only the tilt valve, so we cannot tell you it is CSA listed
- 91 in tall with an open flame: the same wind exposure as every other tower of this shape
- The water box has to be emptied before a freeze or it splits
| Published specification | |
|---|---|
| Rated input | 46,000 BTU/h |
| Published reach | 9 ft radius |
| Dimensions | 32.1" L x 32.1" W x 91.3" H |
| Fuel | 20 lb propane cylinder, not included |
| Safety | Tilt auto-shutoff valve; chain to secure the cylinder |
| Base | Water-fill box for ballast, wheel kit included |
| Maker’s coverage claim | 9.0 ft radius, which is 254 sq ft |
| Safety listing | Tilt auto-shutoff valve; the listing does not name a certifying body |
Who it is for
An open patio where you want the largest honest circle of warmth per dollar and are happy to handle cylinders.
What it is not for
Anywhere enclosed, and anywhere the base cannot be filled with water — an empty ballast box makes this a tall, light, tippy object.
Sources for this entry
2 · Wind, and anywhere with a roof
Dr Infrared Heater Carbon Infrared Patio Heater, 120 V / 1500 W
Radiant heat that a breeze cannot blow out, on a plug. 1,500 W is only 5,118 BTU/h, which sounds like nothing next to a propane tower and lands far more of itself on you.
- Fuel
- Electric
- Output
- 1,500 W = 5,118 BTU/h
- Reach (computed)
- 256 sq ft · 9.0 ft radius
- Cost per hour
- $0.28
What works
- Infrared warms objects, not air, so it is the only heat that survives a breeze — this is the single reason wind changes the whole buying decision
- No combustion means no flue gas, which is what makes it legal and sensible on a screened porch where propane is not
- Three settings matter more than they sound: 900 W costs a third less to run and is enough most evenings
What does not
- 1,500 W is 1,500 W. Nothing at this wattage heats faster than anything else at this wattage; the differences between electric heaters are beam shape and build, not power
- It heats what it points at. Step out of the beam and you are cold immediately — this is a fundamentally different experience from a tower
- A 120 V plug-in unit is capped by your circuit, not by the maker. See why 1,500 W is the ceiling
| Published specification | |
|---|---|
| Rated power | 1,500 W at 120 V |
| Settings | 900 W / 1,200 W / 1,500 W |
| Element | Carbon infrared lamp |
| Reflector | Mirror aluminum, 90% reflectivity per the maker |
| Housing | Anodized aluminum, rated for outdoor use |
| Mounting | Wall and ceiling brackets plus remote in the box |
| Maker’s coverage claim | None published — the reach figure above is ours |
| Safety listing | ETL listed, per the maker's published product data |
Who it is for
A covered patio, pergola or screened porch where you can mount it overhead and point it at where people sit, and anywhere wind ruins a flame.
What it is not for
A big open patio with nowhere to mount it. Radiant heat needs a line of sight and a place to hang from.
3 · One table, four people
Hiland HLDS032-BBS Tabletop Propane Patio Heater
11,000 BTU heats a table, not a patio, and being clear about that is the whole point. For a bistro table on a balcony it is the right size and nothing bigger fits.
- Fuel
- Propane
- Output
- 11,000 BTU/h
- Reach (computed)
- 550 sq ft · 13.2 ft radius
- Cost per hour
- $0.32
What works
- Runs off a 1 lb canister, which makes it the only heater here you can carry out to a table and back with one hand
- 11,000 BTU is honest for the job: our reach arithmetic puts that at roughly a table's worth of warmth, and the unit does not pretend otherwise
- A burner screen guard on a table-height heater is a genuine safety feature, not a spec-sheet line
What does not
- 1 lb canisters are the most expensive propane per BTU you can buy — get the 20 lb adapter hose if you use it regularly
- At 38 in on a table, this puts an open flame at seated head height. Placement matters more than with any other unit here
- It will not touch an open patio. Anyone expecting a room-scale effect will be disappointed
| Published specification | |
|---|---|
| Rated input | 11,000 BTU/h, adjustable |
| Height | 38 in |
| Fuel | 1 lb canister or 20 lb cylinder with an adapter hose |
| Safety | Thermocouple, anti-tilt device, burner screen guard |
| Stability | Weight plate in the base |
| Maker’s coverage claim | None published — the reach figure above is ours |
| Safety listing | Thermocouple flame-failure cutoff and anti-tilt device per the listing |
Who it is for
A balcony, a bistro table, or a second heater that warms hands at the table while a tower does the space.
What it is not for
Heating an area. And never indoors, on a covered porch with a low ceiling, or anywhere a tablecloth can reach it.
Sources for this entry
The shortcut
If you would rather not work through six questions: open patio, buy the 46,000 BTU tower. Covered patio or pergola, buy the mounted infrared unit. Balcony or one table, buy the tabletop. Those three cover most of the real cases on this site, and the flagship roundup explains each in full.
Common questions
What should I look for when buying a patio heater?
In order: whether it suits a covered or open space, whether the output matches your area, whether it can be secured against wind, and whether replacement safety parts are available. Output alone is the least useful specification, because it says nothing about where the heat goes.
How do I know what size patio heater to buy?
Measure the seating area, multiply by 20 BTU per square foot, then multiply by 0.65 if there is a roof and by up to 1.4 if it is exposed. If the answer is under about 5,100 BTU/h a single electric unit does it; well above that means propane.
Is a more expensive patio heater worth it?
Sometimes, and not for the reason people expect. Output does not scale with price — every plug-in electric heater is 1,500 W and most towers are 46,000 to 48,000 BTU. What money buys is weather rating, build, controls, mounting hardware and parts availability, and those are worth paying for on anything that lives outdoors.
Read next
Patio heater BTU calculator
Your patio's BTU requirement with every multiplication shown, plus why the published rules disagree.
Every outdoor heating option, in one page
Seven outdoor heating options compared on output, cost and where each genuinely belongs.
Patio windbreaks, and why they beat a bigger heater
Vinyl, mesh and curtains compared, with what enclosing a patio changes about your heater choice.
The best patio heaters, sorted by the patio
Six heaters covering every real patio case, with published output, computed reach and cost per hour.
Patio heaters for a covered patio
The clearance arithmetic for a roofed patio, and the mounted heaters that actually fit.