Browse Taxation

Mortgage Interest Relief at Source (MIRAS): A Historical Tax Allowance in the UK

An in-depth look at Mortgage Interest Relief at Source (MIRAS), a former UK tax allowance for mortgage interest payments.

Mortgage Interest Relief at Source (MIRAS) was a tax allowance introduced in the United Kingdom, which allowed individuals to deduct part or all of their mortgage interest payments from their taxable income. This relief was aimed at easing the financial burden on homeowners and was administered through lending institutions. The scheme was eventually phased out and officially ended in April 2000. This article delves into the historical context, types of MIRAS, key events, detailed explanations, and its eventual phase-out.

Types/Categories of MIRAS

  1. Standard MIRAS: Applied to basic residential mortgages.

  2. Enhanced MIRAS: Offered additional relief for certain categories of borrowers, including first-time buyers.

Mechanism of MIRAS

Under MIRAS, borrowers received tax relief directly through their mortgage payments. The relief was administered by lending institutions, which means the borrower paid mortgage interest net of tax relief to the lender. This was intended to simplify the process for homeowners and to ensure the relief was claimed efficiently.

Calculation

For example, if a homeowner had a mortgage interest payment of £1,000 and the tax relief was 25%, they would effectively pay £750 to the lender, with the £250 relief administered by the lender.

Withdrawal of MIRAS

MIRAS was phased out primarily due to criticisms regarding its cost-effectiveness and its benefit distribution, which was skewed towards higher-income households. It was also seen as contributing to housing market inflation.

Importance

MIRAS was significant in that it marked a substantial government intervention in the housing market to promote homeownership. While it no longer exists, understanding MIRAS offers insights into fiscal policy and its impact on both individual finances and the broader economy.

Considerations

  • Economic Impact: While MIRAS aimed to make home ownership more affordable, some argue it inflated house prices by increasing demand.

  • Equity Issues: The relief was more beneficial to higher-income households, who had larger mortgages and higher marginal tax rates.

  • Tax Deduction: A reduction of taxable income allowed by law for certain expenses or contributions.

  • Mortgage Relief: A general term encompassing various forms of financial assistance for mortgage payers.

What was the main purpose of MIRAS?

The main purpose of MIRAS was to promote home ownership by reducing the tax burden on mortgage interest payments.

Why was MIRAS withdrawn?

MIRAS was withdrawn due to criticisms of its cost-effectiveness and fairness, and its contribution to housing market inflation.

  • [Mortgage: A Loan Secured by Real Property]({< ref “/mortgages-and-real-estate-finance/mortgage” >} “Mortgage: A Loan Secured by Real Property”)

  • [Amortization Schedule: The Payment-by-Payment Map of a Loan]({< ref “/mortgages-and-real-estate-finance/amortization-schedule” >} “Amortization Schedule: The Payment-by-Payment Map of a Loan”)

  • [Loan-to-Value Ratio]({< ref “/mortgages-and-real-estate-finance/loan-to-value-ratio” >} “Loan-to-Value Ratio”)

  • [Fixed-Rate Mortgage: Meaning and Borrower Tradeoff]({< ref “/mortgages-and-real-estate-finance/fixed-rate-mortgage” >} “Fixed-Rate Mortgage: Meaning and Borrower Tradeoff”)

Revised on Monday, May 18, 2026