- Instantly: steam at the surface, or crushing a bug you can see. Steam only works where it touches.
- Within minutes: a 60°C wash or a hot tumble dryer (run it for at least 30 minutes to be sure, including eggs).
- Slowly: freezing at -18°C for at least 4 days, diatomaceous earth over days to weeks, starving them inside a sealed encasement over months.
- Not reliable: rubbing alcohol (fire risk), tea tree or lavender oil, bleach, baking soda, ultrasonic plug-ins.
The honest answer is that nothing kills every bed bug in a room instantly. Bugs and eggs hide in seams, joints and cracks where sprays and steam do not reach. The plan that works is: kill what you can reach with heat, remove what you can by vacuuming, and seal the mattress so the rest cannot feed.
What should I use on this?
Every method compared
| Method | Kills adults | Kills eggs | Speed | Verdict |
|---|---|---|---|---|
| Steam | Yes, on contact | Yes, on contact | Instant where it touches | Great for seams and frames, slow passes |
| 60°C wash + hot dry | Yes | Yes | One cycle | Best for anything washable |
| Professional heat | Yes | Yes | One visit | Best for heavy infestations |
| Freezing (-18°C) | Yes | Yes | At least 4 days | Good for small items only |
| Professional insecticide | Yes | Not always | 2 to 3 visits | Works, needs follow-ups |
| Shop-bought sprays | Some, on contact | Rarely | Varies | Bugs often resistant, can scatter them |
| Diatomaceous earth | Yes, slowly | No | Days to weeks | Support only, keep it dry and thin |
| Full-zip encasement | Yes, by starving | Traps hatchlings | Months | Essential for the mattress |
| Rubbing alcohol | Some, on contact | No | Instant if soaked | Not recommended: fire risk |
| Essential oils, bleach, baking soda | Unreliable | No | n/a | Don't waste money |
Why "instant" is the wrong goal
Most people who search for an instant fix have just seen a bug. Killing that one bug is easy. The problem is the others you cannot see, and the eggs, which hatch over the next 1 to 2 weeks. That is why one spray session rarely ends a problem and why professionals plan repeat visits.
The mattress is where most bugs live, and it is also the hardest item to treat fully. Sealing it in a full-zip encasement turns it from a hiding place into a trap: any bug inside cannot feed, and any bug outside has nowhere to hide on its smooth surface.
Frequently asked questions
What temperature kills bed bugs?
Bed bugs and eggs die quickly at 60°C. They die more slowly at lower temperatures from around 45°C upwards, which is why professional heat treatments hold rooms at high temperatures for hours.
Does a hair dryer kill bed bugs?
It can kill a bug it blows on directly, but it is more likely to scatter them. Use steam or a hot tumble dryer instead.
Does vinegar kill bed bugs?
Only if a bug is soaked in it, and it does not kill eggs. It is not a treatment.
Can I just throw the mattress away?
You can, but bugs in the frame, room and carpet will move onto the new one. Treat the room, then seal the mattress you have, or the new one, in a full-zip encasement.
Turn the mattress into a trap
A full-zip encasement starves the bugs you can't reach and keeps new ones out. From £149.
Shop the bed bug encasement Protect the whole bedWritten by Richard Williams, founder of iDustMite, former NHS worker, guest speaker at the Allergy UK Show in 2025 and 2026, and adviser on over 1,000 one-to-one bedroom consultations. Reviewed October 2026.
