The update means that the loan cap of £700,000 has been removed and the lender can lend up to £3m.
The large MUFB deals are available for five to 10 units and are available for individuals and corporate borrowers.
The deals are eligible for purchase and remortgage, and the maximum loan to value (LTV) is 75%.
The semi-commercial product has two- and five-year options, with the initial rate of 7.25% and 7.19%, respectively.
The maximum loan to value (LTV) is 75%, the maximum loan is £2.5m, subject to LTV and property limits and can be used for purchase or remortgage.
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The product can be used on semi-commercial properties where the commercial element does not exceed 60% of the total property and the residential element is no more than 80%.
Marylen Edwards, director of mortgages at MT Finance, said: “We are excited to introduce more flexible criteria for our large MUFB product and to expand our buy-to-let offering with the launch of our new semi-commercial product.
“These developments are a direct result of our ongoing dialogue with intermediaries and our commitment to providing solutions that meet the evolving needs of the buy-to-let market. We believe these enhancements will provide valuable opportunities for property investors.”
MT Finance recently upsized its forward flow agreement with JPMorgan by £1bn, bringing the total size to £2.5bn.
The firm has also increased its maximum LTV for its buy-to-let houses in multiple occupation (HMO) deal to 80% and upped the maximum LTV for automatic valuation models to 65%.