Phillip Cutter, who runs freehold pub the Gardeners Arms in Norwich (known locally as the Murderers), totted up the average number of pints he served a day, worked out how many that would be a week then multiplied it by the average 48 weeks he works a year.
Local brewery Woodforde's created a special beer, 'One in a Phillion', to mark the occasion.
Cutter said he had seen some dramatic changes in the industry since starting at the pub as a glass collector almost 30 years ago.
"It's strange - when I first started, it was just a sixth-form job and I'd never have believed I'd end up spending 28 years here but, now, it's part of my life. The industry's changed so much, and although we're still a busy city centre pub, there's so much more to keep people at home then there used to be. When I was growing up, it was rare to see any alcohol sold in supermarkets."
He advised other licensees hoping to stay in the industry as long to invest in their pubs as much as possible.
"You've got to be committed and you've got to keep investing. It can be very difficult, but not spending money on your pub becomes a vicious circle. We recently spent £10,000 having the front of the pub repainted and although it sounds a lot, I think a lot of licensees neglect the exterior.
"Once people are inside they're going to spend money but you need to get them in."
The Gardeners Arms took home the award for Best Sports Pub at the 2015 Great British Pub Awards.