Meanwhile, the number of Post Offices open on Sundays has reached 3,000, with the firm bidding to become the largest retail network doing business on a Sunday in 2016.
A total 5,000 branches have also been modernised this year, at a rate of 10 a day, delivering an extra eight million opening hours.
Branches have opened this year in a butcher's, a baker's and a shop making candle holders.
A new branch in Huby near York is run from a not-for-profit community shop by over 400 villagers, opened with help from the Post Office's £20 million community fund.
Branches have also opened at Baltonsborough Farm Shop near Glastonbury, a farm shop in Bergh Apton, Norfolk, the Badger Hounds pub in Hinterwell, Yorkshire, a church in Stow, Lincolnshire, a fish and chip shop in Allonby, Cumbria and a pet shop in Holmbush, St Austell, Cornwall.
In a different twist to the trend, a local town library moved into the Post Office in Ashburton, Devon, in what used to be a kitchen.
Kevin Gilliland, network and sales director at the Post Office, said: "Our modernisation programme has continued apace during 2015.
"We reached a major milestone of over 5,000 branches converted into new modern retail outlets, with over 3,000 open seven days a week.
"Three years into the programme we have now delivered an eight million extra opening hours for customers to visit our branches.
"The Post Office is operating in a rapidly changing retail market and customers rightly expect to be able to access services when they need them.
"We'll be working hard in the coming year to make sure customers across the UK whether using branches to withdraw cash or pick up online shopping have as easy access as possible to our services."