What Are the Tax Implications of Switching From a Repayment to an Interest-Only Mortgage Mid-Term? Deciding to switch your mortgage from a capital repayment structure to an interest-only basis mid-term is a significant financial maneuver. Homeowners and property investors alike often consider this transition when they need to lower their monthly outgoings to improve immediate cash flow, perhaps due to a temporary change in personal circumstances or an unexpected rise in the cost of living....