The short answer
No. The grey squirrel is a listed invasive non-native species, and it is an offence to release one into the wild after trapping it, or to allow one to escape. That applies whether the release would be in your garden, in a local park or many miles away.
Why grey squirrels are treated differently
Grey squirrels were brought to Britain from North America in the late 1800s. They have since replaced the native red squirrel across most of England, partly by outcompeting it for food and partly by carrying squirrelpox, a virus that rarely harms greys but is usually fatal to reds. They also strip bark from young trees. That is why the law treats them as an invasive species rather than protected wildlife. None of this makes an individual squirrel a bad animal; the rules are about the species and its effect on native wildlife.
What the law says
Under the Invasive Alien Species (Enforcement and Permitting) Order 2019, it is an offence to release a grey squirrel into the wild or to allow one to escape. Before that, releasing grey squirrels was already an offence under the Wildlife and Countryside Act 1981. This is a summary, not legal advice. Rules on keeping, breeding and moving the species also exist, and anyone in doubt about their own situation should take proper advice.
What happens once one is trapped
Because a trapped grey squirrel cannot lawfully be let go, in practice it is humanely dispatched. Animal welfare law also applies to how a trapped animal is treated, so it must not be left to suffer. This is part of why squirrel control is best left to a pest controller rather than tackled with a trap bought online.
If you trap one yourself
The same law applies to everyone, not just pest controllers, including a neighbour who offers to lend you a trap. If you catch a grey squirrel, you cannot release it, and you are responsible for its welfare while it is in your hands. Anyone not prepared to deal with that outcome should not set a trap in the first place.
What about red squirrels?
Red squirrels are protected by law, but they are not found in London; the remaining populations in England are far from the capital. Any squirrel in a loft in Brent will be a grey. Some grey squirrels have darker or ginger-tinged fur, particularly in summer, which can lead people to think they have seen a red, but the size and build give it away.
Poison is not the answer either
Rat and mouse poisons are sold for rats and mice. Use any pest product only as its label allows, and remember that an animal dying out of reach in a roof space brings a smell and hygiene problem of its own. Pets and children can also reach bait that has been put down carelessly, which is a particular worry in family homes like many in Sudbury.
Releasing does not fix the loft
Even if release were allowed, it would leave the real problem in place: an open gap in the roof that the next squirrel will find. See why squirrels keep returning to the same loft and how to stop them getting back into your roof. Closing that gap, once the loft is empty, does more to protect the house than anything that happens to one squirrel.
Getting help within the law
If you have heard squirrels overhead, start with how to know if squirrels are in your loft. Lofts in the interwar houses of Kingsbury and the larger period homes of Dollis Hill are typical places to find them. Squirrel control in Brent is a £280 trapping service, and you can book squirrel control online.
