The planned new swimming pool and leisure centre in Exeter city centre could cost an extra six million pounds.
Councillors have been told that the addition of extra facilities would generate more income from the complex - due to be built on the site of the bus station.
The extras include more fitness stations, a larger soft play area and a much bigger spa area with saunas, steam rooms and a hydrotherapy pool.
Councillors have been told this won't cost the taxpayer any more money as the extra will come from developer contributions and capital receipts