Gervais, 60, had said the new third series of After Life would be the end of the show, but pushed on whether it was absolutely the last he told BBC Radio 5's Headliners podcast: "Well, I can't say that. I can't say that about anything."
He added of making another season: "It is tempting. And it makes no sense to end it, It makes absolutely no sense.
"It's the most popular it's ever been. You get paid more as the seasons go along. It makes no sense at all other than I think it's the right decision artistically."
Gervais famously ended his sitcom The Office after just two series and a Christmas special, only to revisit the character of David Brent again 10 years later in 2013, and to make a spin-off movie in 2016.
The Extras star has also addressed why the characters of Roxy and Sandy are missing from the final series of After Life.
Comedian Roisin Conaty starred as sex worker Roxy in the sitcom, who had started dating postman Pat in series two.
And Mandeep Dhillon played reporter Sandy who worked with Tony at the local paper.
Gervais told Digital Spy: "Mandeep couldn't do it because she was filming, so I'd sort of written her bit and I had time to change them. With Roxy we thought there wasn't quite the story there. It's you know, it's a mutual decision, I didn't write them out."
He added: "That was fine because Roxy wasn't in it much, you know, so I got around that with giving the story sort of through [Pat] the postman [played by Joe Wilkinson]. But Sandy I had time to rewrite it, write her out and put Coleen [Kath Hughes] in her place."
Watch: Ricky Gervais responds to government's partygate