The cash will be invested over the next three years as the grocer seeks to expand its footprint in the UK from its existing 264 outlets.
Managing director Mark Price unveiled the plans to Prime Minister David Cameron during a meeting at the Conservative Party conference.
Many of the new stores will be in the north of England and Scotland as the chain looks to grow beyond its southern stronghold.
Its drive north includes building a £35m regional distribution centre in Chorley, Lancashire, which will open next autumn.
This will give Waitrose the capacity to deliver to 80 stores in the north and Scotland.
Price said: “This new distribution centre will support the growth of our business, be a boost for the north-west, create 600 new jobs for the region and make it possible for us to invest £1bn in Britain over the next three years.”