It is switching from a range of drinks including Champagne and wheat beers, which are produced in France and Germany.
Wetherspoon will replace Champagne with sparkling wines from the UK; Denbies Sparkling Whitedowns Brut and Whitedowns Rose Brut as well as Hardys Sparkling Pinot Chardonnay from Australia.
The pubs will also serve wheat beers from the UK; Blue Moon Belgian White, Thornbridge Versa Weisse Beer and SA Brains Atlantic White.
Wetherspoon will continue to serve Kopparberg cider from Sweden.
Kopparberg has confirmed that it will be producing its cider in the UK post-Brexit.
Alcohol-free Adnams Ghost Ship will replace Erdinger alcohol free beer from Germany.
Wetherspoon chairman Tim Martin said: “This move helps us to broaden our horizons so that we create an improved offer for the two million customers who visit our pubs each week.
“It is the start of a review all products in the next six to 24 months, with the object of making our business more competitive.
“The EU’s customs union is a protectionist system which is widely misunderstood.
“It imposes tariffs on the 93 per cent of the world that is not in the EU, keeping prices high for UK consumers.
“Tariffs are imposed on wine from Australia, New Zealand and the US, and also on coffee, oranges, rice and more than 12,000 other products.
“There will be an inevitable transfer of trade post-Brexit to countries outside the EU, which will reduce prices in shops and pubs.
“The products we are now introducing are at lower prices than the EU products they are replacing.
“We intend to honour existing contracts with EU suppliers, some of which have several years to run.
“ However, we are starting to make the transition to non-EU trade now.
“Our biggest bottled cider supplier is the excellent Kopparberg of Sweden.
“Kopparberg has said that it will transfer production to the UK post-Brexit.
“In similar situations we will work closely with suppliers of niche products.
“Brexit will create big marketing opportunities for UK and non-EU producers, which Wetherspoon is keen to encourage.
“To maximise the opportunities from Brexit the UK must follow free trading nations like Australia, New Zealand and Singapore by ending tariffs.
“Ending tariffs will not result in any reduction in government income, since tariffs collected in the UK are sent to Brussels.
“Free trade and the ending of tariffs will reduce prices, boosting living standards and helping business.
“This will not be possible if we remain in the EU’s customs union.
“Ending tariffs will also help to minimise border inspections, and will benefit poorer countries in Africa and elsewhere, which are penalised by EU protectionism.”