The Heathrow-to-Gatwick transfer is the classic airport-to-airport connection, looping anticlockwise around the southern M25 for about 45 miles between London’s two biggest hubs. Travellers with a self-connection between flights lean on it heavily, because a single door-to-door taxi is far simpler than dragging luggage through trains or coaches.
The catch is the M25 itself, which can be heavily congested and turn a straightforward drive into a slow crawl. For a tight connection, allowing generous time and comparing an estimate in advance is essential.
Typically 60–90 minutes for the roughly 45-mile M25 loop, but the M25 is prone to delays. For a flight connection, allow much more time than the best-case figure.
For a tight or late connection with luggage, a door-to-door taxi is more flexible and direct. Coaches are cheaper but less frequent and slower. Compare the estimate for your timing.
Yes — note your Heathrow terminal and your Gatwick terminal (North or South) so the licensed taxi partner picks up and drops off in the right places.