Central heating is expensive to run. Some rooms never get warm enough. Thermostats control the whole house, but you only occupy one or two rooms at a time. Your home office is freezing while you work. The basement stays cold no matter what.
Space heaters target specific areas with supplemental heat, reducing your overall heating costs while keeping you comfortable where it matters.
But choose wrong and you’re either burning through electricity without feeling warmer, creating fire hazards, or dealing with a heater that can’t handle your actual needs.
We’ve researched space heaters extensively to help you understand what works for your specific situation.
Types of Heaters: The Real Differences
Ceramic Heaters
Use ceramic plates that heat up when electricity passes through. A fan blows air across the hot ceramic.
Fast heating, portable, safe (ceramic doesn’t glow red hot), automatic shutoff features common, relatively quiet.
Best for: Quick personal heating, offices, small to medium rooms
Oil-Filled Radiators
Sealed columns filled with oil. Electric heating element warms the oil, which circulates and radiates heat. No fan.
Silent operation, gentle consistent heat, stays warm after shutoff, very safe (no exposed elements), energy-efficient for extended use.
Best for: Bedrooms, living rooms, anywhere you want silent consistent heat
Infrared Heaters
Emit infrared radiation that heats objects and people directly, not the air.
Instant warmth, efficient (doesn’t waste energy heating air that escapes), quiet operation, safe for indoor use.
Best for: Spot heating, outdoor patios, garages, workshops
Convection Heaters
Heat air that rises naturally, creating circulation. Panel-style or baseboard designs.
Even heating, silent (no fan), wall-mountable options, energy-efficient for whole-room heating.
Best for: Consistently heating entire rooms, supplementing baseboard heat
Propane/Gas Heaters
Burn propane or natural gas for heat. Indoor-safe models exist but require ventilation.
Powerful heating, works during power outages, efficient for large spaces like garages.
Best for: Garages, workshops, construction sites, emergency backup heat
Micathermic Heaters
Combine convection and radiant heating using thin mica stone panels.
Fast heating, lightweight, space-efficient, quiet, energy-efficient.
Best for: Apartments, bedrooms, rooms with limited floor space
Understanding Wattage and Heat Output
Space heaters are almost always 1500 watts max. That’s limited by standard 120V household outlets (drawing more risks tripping breakers).
1500 watts = roughly 5100 BTU of heat output. That’s the ceiling for plug-in space heaters.
How much can 1500 watts heat?
- Small room (100-150 sq ft): Easily
- Medium room (150-300 sq ft): Adequately
- Large room (300-400 sq ft): Struggles, especially if poorly insulated
- Very large room (400+ sq ft): Insufficient as primary heat
Space heaters work best as supplemental heat in rooms where you spend time, not as primary heating for entire homes.
The myth that higher wattage means better heating? False for space heaters. They’re all capped at 1500W. Marketing differences are about features, safety, and distribution—not more heat.
Energy Efficiency Reality
Space heaters convert electricity to heat at nearly 100% efficiency. Every watt of power becomes heat. A $30 heater and a $300 heater produce the same amount of heat from 1500 watts.
But “efficiency” is more nuanced:
Oil-filled radiators retain heat longer, meaning they cycle off more often while maintaining temperature. This can reduce energy use by 10-15% compared to constant-fan ceramic heaters.
Infrared heaters heat you directly instead of heating all the air in a room. If you’re sitting in one spot, this uses less energy than heating the entire space.
Programmable thermostats prevent overheating and wasted energy by maintaining target temperature exactly.
The real efficiency question isn’t the heater—it’s whether using a space heater saves money versus central heating.
Running a 1500W heater 8 hours: Cost = 1.5 kW × 8 hours × $0.12/kWh = $1.44/day = roughly $43/month
If that lets you turn down your thermostat by 3-5 degrees and heat only the room you occupy, you save money. If you run it while keeping central heat at the same temperature, you’re adding costs.
Safety: The Non-Negotiable Factors
Space heaters cause roughly 25,000 house fires annually in the US. Most are preventable with basic precautions.
Must-have safety features:
Overheat protection: Automatically shuts off if internal temperature gets too high
Tip-over switch: Cuts power immediately if knocked over
Cool-touch exterior: Housing stays safe to touch even during operation
Auto-shutoff timer: Prevents all-night operation unattended
ETL or UL certification: Third-party safety testing verification
Safe usage rules:
Keep 3 feet clearance from curtains, furniture, bedding, papers—anything flammable
Never run unattended while sleeping or away from home (despite what marketing says about “safe overnight use”)
Plug directly into wall outlet—never extension cords or power strips (fire risk from overload)
Place on flat, hard, stable surfaces—not beds, couches, or carpets
Keep away from water—never use in bathrooms unless specifically rated for it
Turn off when leaving the room
Don’t run continuously for 8+ hours—let them cool down periodically
Noise Levels: What to Expect
Silent heaters:
- Oil-filled radiators: 0 dB (no moving parts)
- Infrared heaters: 0-10 dB (minimal electronics noise)
- Micathermic: 0-10 dB
Quiet heaters:
- Ceramic with fan: 40-50 dB (white noise, tolerable)
- Convection heaters: Under 45 dB
Noisy heaters:
- Fan-forced ceramic on high: 50-60 dB (noticeable)
- Old-style coil heaters with fans: 55-65 dB (disruptive)
For bedrooms, choose fanless options. For offices or living spaces where minor background noise doesn’t matter, fan-based heaters are fine.
Heating Speed vs Sustained Comfort
Fast heating (ceramic, infrared):
You feel warmth within seconds to minutes. Great for quick bursts or warming up fast when you enter a cold room.
Slow heating (oil-filled, micathermic):
Takes 15-30 minutes to reach full heat output. Better for maintaining comfort over hours without the constant blast of a fan.
Match this to your usage:
- Home office you occupy all day: Slow, sustained heater
- Bathroom for morning shower: Fast ceramic heater
- Bedroom overnight: Oil-filled for silent, consistent warmth
- Garage workshop for a few hours: Infrared for quick spot heating
Sizing for Your Space
Despite wattage limits, some heaters distribute heat better than others.
Room Size Guidelines (well-insulated rooms):
100 sq ft or less:
Any 750-1000W heater works. Consider a small ceramic or infrared unit.
100-200 sq ft:
1500W ceramic heater with fan, or oil-filled radiator. Most bedrooms fall here.
200-300 sq ft:
1500W oil-filled radiator or larger ceramic heater. May take 30-45 minutes to warm initially.
300+ sq ft:
Single space heater struggles. Consider two smaller units in different areas, or address insulation issues.
Poorly insulated or drafty spaces:
Cut expected coverage in half. A heater rated for 200 sq ft might only comfortable heat 100 sq ft in a drafty basement.
High ceilings (over 8 feet):
Heat rises. Standard space heaters struggle. Infrared works better (heats objects, not air that rises away).
Special Use Cases
Bathroom Heating:
Must be rated for bathroom use (moisture resistant). Mount away from tub/shower. Never use standard space heaters in bathrooms (electrocution risk).
Garage/Workshop:
Propane or heavy-duty infrared heaters work best. Standard space heaters struggle in uninsulated, drafty spaces.
Under-Desk Heating:
Personal ceramic heaters work well at 500-750W. Don’t need full 1500W to warm your legs.
Outdoor Patios:
Propane or electric infrared heaters only. They heat people directly, not the open air.
RVs and Campers:
Propane heaters designed for RVs, or low-wattage electric heaters that won’t trip RV breakers.
Basement:
Oil-filled radiators or infrared. Basements are typically damp and cold—consistent heat works better than quick bursts.
Smart Features Worth Considering
Digital thermostats:
Maintain precise temperature. Worth it for extended use or overnight heating.
Programmable timers:
Set heating schedules. Warm your bathroom before your morning shower, turn off after you leave for work.
Remote controls:
Adjust settings without getting up. Minor convenience but appreciated when you’re already warm and comfortable.
Eco modes:
Adjust power consumption to maintain temperature efficiently. Can save 10-20% on energy costs.
Oscillation:
Ceramic heaters that rotate distribute heat more evenly. Useful in larger rooms.
App control:
Turn on heat before arriving home. Monitor energy use. Only valuable if you’re tech-focused.
Common Mistakes That Cost You Money
Running heaters in empty rooms. They don’t “pre-warm” spaces efficiently. Turn on when you enter.
Heating the whole house with space heaters. Central heating is more efficient for whole-home heating. Space heaters shine for zone heating.
Blocking airflow around the heater. Furniture or walls too close reduces efficiency. Give them clearance.
Using the wrong type for your need. Fan heater in a bedroom keeps you awake. Oil radiator in a bathroom takes too long to warm up. Match heater to usage.
Expecting them to overcome major insulation problems. Fix drafts and insulation issues first. Heaters can’t overcome major heat loss efficiently.
Never cleaning them. Dust accumulation reduces efficiency and creates fire risk. Clean vents and surfaces monthly.
What We Look For in Reviews
Actual heating performance. Does it warm the advertised space in reasonable time? User reports of real-world effectiveness.
Build quality and longevity. Does it survive multiple winters or fail after one season?
Safety features in practice. Do tip-over switches actually work? How sensitive is overheat protection?
Thermostat accuracy. Does it maintain set temperature or oscillate wildly?
Noise levels by type. Manufacturer specs versus real user experience in quiet rooms.
Energy consumption patterns. How often does it cycle? Does eco mode actually reduce costs?
Customer service quality. Warranty response, defect handling, replacement parts availability.
Making Your Decision
Measure your space. Identify primary usage (quick warmth vs all-day heating). Consider noise tolerance.
Choose heater type based on your specific need:
- Fast heating: Ceramic
- Silent operation: Oil-filled
- Spot heating: Infrared
- Consistent room heating: Convection or Micathermic
Verify safety certifications (ETL/UL). Check for overheat protection and tip-over switches—non-negotiable.
Set a realistic budget. Quality heaters last years; cheap units often fail within one season.
Then review our detailed comparisons. We identify which models deliver actual value and which sacrifice safety or performance for low prices.
Staying warm in cold spaces is solvable. It just takes the right heater for your specific situation.