Pub chain receives double boost in summer.
Wetherspoon expects a "reasonable outcome" for the financial year ending this month but said the main challenges facing the group were continuing cost pressures resulting from government legislation.
It has already warned it will the slow the pace of new pub openings in the next year to between 20 and 30 sites as it grapples with a pounds 50m increase in its annual tax bill, including rises in excise duty.
Although the recent special events were a major driver of the sales boost, the chain's chairman Tim Martin said he was hopeful that people may be starting to return to pubs following the smoking ban.
He said: "Our sales have been growing at about 2% over recent years, which is a little less than inflation, so we are glad to see a pick-up. My own theory is that the industry may be starting to see a bit of a rebound after the smoking ban.
"Possibly we are now seeing a bit of a revival as smokers get used to going outside and people who don't like smoking start to come back."
He added that similar trends had been seen in parts of the United States where bars had taken a while to recover from smoking bans.
Mr Martin said the Olympics may also prove to be a temporary boost to the sector, although its impact was hard to predict.
[bar] Events like the Diamond Jubilee and Euro 2012 had a positive impact on footfall at pub chain JD Wetherspoon