Certain deals come without an arrangement fee and include a free valuation and legal package.
The new deals will be available online or over the phone from February 14th 2014.
John Willcock, head of mortgages at Post Office, said: “Post Office’s mortgage offering has gone from strength to strength since its launch. We constantly review our product range and move quickly to respond to customer demand and changes in the market. There has been a significant increase in the demand for buy-to-let mortgages in the last 12 months as more borrowers begin to consider the rental market.
“We are committed to offering all borrowers competitive mortgages that address their needs – whether they’re a first-time buyer, someone looking to move up the property ladder, or someone looking to take out their first buy-to-let mortgage.”
Mike Joyce, director consumer banking at Bank of Ireland UK, added: “We are delighted to enhance the range of products offered through our longstanding partnership with the Post Office. Bank of Ireland UK is committed to introducing innovative and competitively priced products to benefit our customers, as well as generate business growth and long-term value for both organisations.”