https://www.met.police.uk/contact/how-to-make-a-silent-999-call/#:~:text=Call%20999%20from%20a%20mobile,your%20call%20could%20be%20ended. *How to make a silent 999 call* If you're in danger, call 999 and try to speak to the operator if you can, even by whispering. You may also be asked to cough or tap the keys on your phone to answer questions. Call 999 from a mobile If you don't speak or answer questions, press 55 or tap when prompted and your call will be transferred to the police. The police will usually be able to find your location. If you don't press 55 or respond, your call could be ended. Call 999 from a landline If you don't speak or answer questions and the operator can only hear background noise, they'll transfer your call to the police. If you replace the handset, the landline may remain connected for 45 seconds in case you pick it up again. Calling 999 from a landline automatically gives the police information about your location.