As a result of the agreement, members of the club will have access to the lender’s range of products.
The building society offers a standard residential mortgages, later life, buy-to-let and holiday-lets, expats, self-builders and first-time buyer products.
It will also lend to British expats living in any country except sanctioned or war zones with an LTV up to 80%.
Melanie Spencer, head of MCI Mortgage Club, said: “We are continuing to expand our lender panel and building societies are always welcome as they offer niche products.
“Ipswich has a great mortgage range and caters for all sorts of borrowers giving our members alternative options for their clients.
“Our members can easily apply for Ipswich’s products via our slick and efficient CRM system and digital mortgage platform.”
Charlotte Grimshaw, head of mortgage sales at Ipswich Building Society, added: “We are excited to be launching with MCI Club, having worked closely over the last few months to develop our partnership.
“Through our range of lending solutions and by employing an expert manual underwriting system we are able to assist brokers with their slightly unusual or complex cases.
“We look forward to helping shape cases for MCI Club members going forward.”