Remortgaging a leasehold flat with a short lease can be challenging. Many lenders have minimum lease requirements when considering a mortgage or remortgage application. If a lease is nearing its end, typically with less than 70 years remaining (though this can vary between lenders), it may be considered a higher risk. The property's value might depreciate faster as the lease shortens, and it could be more difficult to sell. If you're considering remortgaging, it might be worthwhile to look into extending the lease first, though this can be costly.