Instructions:If you're a new customer, there's currently a hot code available that gets you £25 off when you spend at least £50 on any booking worldwide.
You'll need to pay via Paypal and enter the code PAYPALSTAY25 online at the checkout. The booking must be confirmed by your Airbnb host by Mon 31 Oct and as it can take a couple of days for confirmation, give yourself some leeway. Your stay can be any time before or after this date.
You can only use the code once and it can't be used with any other codes. See the full T&C at the link below.