The 84-year-old will hang up his apron on April 8 and said it would be an emotional day.
Jackson's Chippie, known locally as Jackos, first appeared in Market Street before moving to its current location, further down the same road, in 1982.
After leaving the air force, Jackson said he had been short of a job until a friend of his dad said he could work peeling potatoes in a chip shop.
He said it seemed to suit me and I got all my money together, sold my scooter and bought my own place.
Fish and chips should be the cheapest meal out, but it's a struggle for a lot of people, he said.
My fish costs went up double in 2022. I've been quoted for gas and it's quadrupled. Anybody can stand and give the stuff away, but you still need to make a bit of profit at the end of the day. Jackson said he would feel emotional when he tips the last batch of chips into the fryer.
He said the time's right and you've got to have a bit of life afterwards.
I got through my 60 s like a piece of cake, I sailed through my 70 s quite right, but when I hit 80 I went a bit achy.