Still cockroaches after pest control. What’s going wrong?

You paid, you cleaned, you emptied the cupboards, and they are still there. That is exhausting, and if it is wearing you down, that is a normal reaction to living with this. A clean flat does not protect you from German cockroaches, and nothing here is your fault. When treatment stalls, it is usually down to a handful of causes, and most of them can be checked.

Is it normal to need more than one visit?

Yes, with German cockroaches it usually is. Egg cases are well protected and can hatch after a treatment, so seeing young ones in the weeks after a visit does not mean it failed. What should change is the trend. Over several weeks, the numbers should fall.

If you are still seeing lots of small ones after weeks of visits, or the counts are not moving, something below is likely getting in the way.

The usual reasons treatment stalls

• Sprays on top of bait. Your own spray, or a strong cleaner, on or near the bait can put cockroaches off it. Wiping the bait away does the same.
• No growth regulator. Without one, young cockroaches that survive grow up and breed again.
• The hiding place was never reached. Behind a built-in dishwasher, inside an appliance, in the space behind the kickboards, around pipes in the wall.
• The neighbours are not treated. In a block of flats, treating one flat while the next stays full means a steady supply of new ones.
• Nobody is counting. Without dated trap counts, nobody can tell if it is working or which room is the hot spot.
• The wrong method for the species. Some species, like the smoky brown cockroach, live mostly outdoors and wander in. A spray around the outside helps with those. Indoor German cockroaches need bait inside.
• They stopped eating that bait. It happens. Our page on when gel bait stops working explains what to change.

Where else to look

With a torch, at night: the motor area under the fridge, the back of the cooker, cupboard hinges and door frames, the inside of the microwave and coffee machine, under the sink where the pipes go through the wall, gaps behind loose tiles. Put monitor traps in each spot for a week. The trap with the most catches shows you where they live.

What to ask the company

• Which species is it, and which products are you using?
• Are you using a growth regulator? Where exactly did you place the bait?
• What should I avoid between visits: sprays, cleaners, wiping certain areas?
• How many more visits do you expect, and how will we know it is working?
• Should the flats around mine be treated as well? Can I have that in a written report?

Between visits

1. Stop spraying. It feels like doing something, but it works against the bait.
2. Leave the bait where it is. Clean around it, not over it.
3. Count every week with traps, adults and young ones apart, and keep the dates.
4. Dry and seal. Fix drips, dry the sink at night, and close gaps around pipes. See sealing gaps.

Adding your own products: tell the company first, so nothing clashes with what they used. Follow the label, check the product is allowed where you live, and keep everything out of reach of children and pets.

When it is the building

Signs that it is bigger than your flat: neighbours mention them, you see them in shared hallways or bin areas, or they come back after every round. Then one flat at a time will not fix it. If you rent, put it in writing to the landlord or building manager and ask for adjoining units to be treated together. Our pages on cockroaches from next door and renting with pests explain who to ask where you live.

Your dated counts are your strongest evidence. They turn “it is not working” into something a landlord or company has to answer.