Marriage and Civil Partnership Tax Benefits in the UK 2026/27 — A Complete Overview

Marriage and tax in the UK — the overview

Getting married or entering a civil partnership changes your tax position in several important ways. While the UK broadly taxes individuals rather than households (unlike some other countries), there are specific reliefs, exemptions, and planning opportunities that only become available to married couples and civil partners.

This guide covers every benefit, how to access it, and the less obvious negative effects to watch out for.

Marriage Allowance — up to £252 per year

Marriage Allowance allows the lower-earning spouse to transfer £1,260 of their unused Personal Allowance to their partner, reducing the higher earner's income tax bill by up to £252 per year (£1,260 x 20%).

Qualifying conditions

Both of the following must apply:

• One partner earns below the Personal Allowance (£12,570 in 2026/27) — they are the "transferor"
• The other partner is a basic rate taxpayer with income between £12,571 and £50,270 — they are the "recipient"

If the recipient earns above £50,270 (higher rate), Marriage Allowance is not available.

How it works in practice

The transferor's Personal Allowance is reduced from £12,570 to £11,310 (they give away £1,260). The recipient's Personal Allowance increases from £12,570 to £13,830.

Example:

• Partner A: income £8,000 (£4,570 of their Personal Allowance is unused, so they can afford to give away £1,260)
• Partner B: income £38,000 (basic rate taxpayer)
• Partner B's tax saving: £1,260 x 20% = £252/year

How to apply

The lower earner applies via gov.uk/apply-marriage-allowance. You will need your National Insurance number and your partner's NI number and date of birth.

HMRC adjusts both tax codes. If one partner is on Self Assessment, the adjustment is made through the tax return.

Backdating Marriage Allowance

You can backdate the claim to the earliest eligible tax year in which you were married and met the qualifying conditions — up to 4 tax years back. For a claim made in 2026/27, you can potentially claim back to 2022/23.

Maximum backdated saving: 4 years x £252 = £1,008 (approximately — rates vary slightly by year).

Claims for past years are processed as tax rebates to the recipient.

CGT spousal transfers — no gain, no loss

Transfers of assets between spouses or civil partners who are living together are treated as being made at no gain, no loss for Capital Gains Tax purposes. This means:

• No CGT arises at the time of transfer
• The receiving spouse inherits the original acquisition cost of the asset (not the current market value)

Why this matters

Bed-and-spouse: If one spouse has used their £3,000 Annual Exempt Amount but the other has not, you can transfer a gain-making asset to the spouse before selling, so the sale is made in their name and their AEA is used.

Example:

• Shares worth £20,000, originally bought for £13,000 (gain = £7,000)
• Spouse A has already used their £3,000 AEA
• Spouse A transfers shares to Spouse B (no CGT at this point)
• Spouse B sells the shares: gain = £7,000, AEA = £3,000, taxable gain = £4,000
• CGT at 18% (if Spouse B is a basic rate taxpayer) = £720 instead of £800 (if Spouse A had sold direct at 24% as a higher rate taxpayer, net gain £4,000 = £960)

The additional benefit: if Spouse B is a basic rate taxpayer where Spouse A is a higher rate taxpayer, the same gain is taxed at 18% vs 24% — saving 6 percentage points.

Limit of the relief

The no gain/no loss rule only applies while you are married or in a civil partnership and living together. The rule ceases to apply from the end of the tax year of permanent separation. After that point, transfers between separated but not yet divorced spouses are treated as arm's-length disposals at market value, potentially triggering CGT.

IHT spouse exemption — unlimited

Assets left to a UK-domiciled spouse or civil partner on death are completely exempt from Inheritance Tax, regardless of value. This is one of the most powerful IHT reliefs in the UK tax system.

There is no limit — you can leave an estate of any size to a UK-domiciled spouse with zero IHT on death.

Transferred nil-rate band

When a spouse dies without using all of their nil-rate band (NRB) for IHT purposes, the unused portion transfers to the surviving spouse on their subsequent death.

With a standard nil-rate band of £325,000 (frozen until 2030), a couple can potentially have a combined NRB of £650,000 — meaning the surviving spouse's estate can pass £650,000 free of IHT before the 40% rate applies.

The transfer is claimed by the executors of the surviving spouse's estate at the time of probate. The percentage of unused NRB is transferred — not the cash amount — so the surviving spouse benefits from the NRB at the rate applicable on their own death.

Residence nil-rate band (RNRB)

The Residence Nil-Rate Band (RNRB) adds a further £175,000 per person (2026/27) to the IHT-free threshold, provided:

• The estate includes a residential property (or previously included one)
• The property passes to direct descendants (children, grandchildren etc.)

The RNRB also transfers between spouses, giving a potential combined RNRB of £350,000.

Combined NRB + RNRB for a couple: £650,000 + £350,000 = £1,000,000 — meaning estates worth up to £1 million can potentially pass entirely IHT-free to children on the second death.

The RNRB tapers away for estates over £2 million (£1 for every £2 above the threshold).

ISA Additional Permitted Subscription (APS)

When a spouse or civil partner dies, the ISA savings they held do not lose their tax-free status at death. The surviving spouse can make an Additional Permitted Subscription (APS) to their own ISA equal to the value of the deceased's ISA holdings at the date of death.

Key rules

• The APS is in addition to the normal £20,000 annual ISA allowance
• The APS must be used within 3 years of the date of death (or 180 days after administration of the estate is complete, if later)
• The APS can be invested in the same type of ISA (cash or stocks & shares) or a different type
• The APS effectively extends the tax-free wrapper — preserving tax-free growth and withdrawals for the surviving spouse

Example:

• Deceased spouse had ISA holdings worth £85,000 at death
• Surviving spouse's own ISA allowance for the year: £20,000
• Surviving spouse can invest a total of £105,000 into ISAs in the year of death (or shortly after)
• All £105,000 grows and can be withdrawn tax-free in perpetuity

Pension nominations and spousal benefits

Marriage itself does not automatically mean your pension passes to your spouse — you need to make a nomination of beneficiary (sometimes called an "expression of wishes" or "nomination form") with each pension provider.

For most personal pensions and SIPPs, the pension fund is held in a discretionary trust. The provider uses your nomination to guide who receives the death benefits — but is not legally bound to follow it. Updating your nomination after marriage (and after any divorce or separation) is critical.

Death benefits by pension type

Death in service lump sum (employer life assurance) — typically 3-4x salary — is usually written in trust and passes outside your estate. Ensure your nomination is current.

Married Couple's Allowance (MCA)

The Married Couple's Allowance is an additional tax relief available to married couples or civil partners where at least one partner was born before 6 April 1935 (i.e. aged 91 or over in 2026/27).

For 2026/27:

• Maximum MCA: £11,080
• Minimum MCA: £4,300
• Tax reduction: 10% of the allowance — so maximum tax saving of £1,108/year

The allowance reduces (by £1 for every £2 of income above £37,000) for higher-income claimants, down to the minimum of £4,300.

MCA and Marriage Allowance are mutually exclusive — you cannot claim both. In practice, MCA applies to the older generation where one spouse was born before April 1935.

Potential negative tax effects of marriage

Marriage brings tax benefits but also a few areas where it can complicate matters:

High Income Child Benefit Charge (HICBC)

The HICBC is assessed on an individual basis — if either you or your partner has adjusted net income above £60,000, you must repay Child Benefit at a rate of 1% for every £200 above the threshold. Above £80,000, the benefit is fully repaid.

Marriage itself does not change the HICBC threshold — it remains per-individual, not per-household. However, marriage (and sharing accommodation) may affect Child Benefit eligibility itself in some cases.

Capital Gains Tax cost basis on spousal transfers

While no CGT is triggered at transfer, the receiving spouse inherits the original low cost basis — meaning when they eventually sell, a potentially large gain could be triggered. This is a longer-term consideration if the asset has significantly appreciated.

Joint asset ownership and CGT

If you own assets jointly, the default is equal ownership (50/50 split) for CGT purposes. If you want to split gains in a different proportion (e.g. 90/10 to use the lower-earning spouse's AEA and lower rate), you can declare a different beneficial interest on Form 17 — but this only works for certain assets (not ISAs, bank accounts, or savings). For most assets, the split must genuinely reflect your legal ownership.

Declaration of marriage for tax purposes

Marriage registration in the UK is handled by the General Register Office (births, deaths and marriages). For HMRC purposes, the change in your tax position takes effect from the date of marriage or civil partnership registration. You do not need to formally notify HMRC of your marriage — it will become apparent through your tax return or when you apply for Marriage Allowance. However, you should update your personal details in your Personal Tax Account.

Related calculators

The income tax calculator lets you model your household income tax position and see the impact of Marriage Allowance.

The take-home pay calculator is useful for comparing net income for both partners and planning the most tax-efficient income split.