Could you provide an estimate for the proportion of fares received by Transport for London (TfL) that are paid by residents of London, and could you provide this for each year since 2016?

Unfortunately, it is not possible to distinguish between fares received by Transport for London (TfL) from London residents versus non-London residents.

TfL does not associate the residence of a customer with fares received, whether that is when they purchase a ticket, top-up an Oyster card, or use either pay as you go (PAYG) credit or contactless to travel.

This means that TfL has no reliable way of providing the estimate requested.