Photo by Vitaly Gariev on Unsplash

Financial Planning for Couples UK 2026: How to Use Both Sets of Allowances

Most couples manage their finances individually — separate ISAs, separate pensions, separate tax returns. That approach works, but it leaves a substantial amount of legally available tax efficiency unclaimed. Married couples and civil partners in the UK have access to a set of allowances, exemptions, and transfer rules that single individuals simply do not have — and using them intelligently can be worth thousands of pounds per year.

None of these strategies involve tax avoidance. They are built into the UK tax system by design — the government explicitly provides them. The challenge is that most couples either do not know they exist, or know about them individually but have never sat down to apply them as a combined household strategy.

This guide covers every major tax planning opportunity available to UK couples in 2026: double ISA allowances, no-gain-no-loss asset transfers, pension contribution strategies, the Marriage Allowance, income splitting, CGT planning, inheritance tax advantages, and the critical differences between what married couples have access to versus those who are living together without a legal partnership.

Double ISA Allowances: £40,000 Per Year Tax-Free

Every UK adult has an annual ISA allowance of £20,000. Married couples and civil partners each have their own separate allowance — they cannot be combined into a joint ISA, but they can be funded independently to shelter a combined £40,000 per year from tax.

This is straightforward in principle but frequently underused in practice. If you're a married couple, you can put up to £40,000 in ISAs between you tax-efficiently. If one partner has maximised their own ISA allowance, the other may not have — and any earnings or assets the higher-saving partner transfers to the lower-saving partner can be used to fund that person's ISA without triggering a tax charge between spouses.

The practical application: if you have £30,000 of savings to shelter and you have already used your own £20,000 ISA allowance, your spouse or civil partner has £20,000 of ISA allowance available. Transferring £10,000 to them and funding their ISA with it costs nothing in tax between spouses and permanently shelters those savings from income tax and capital gains tax.

From 6 April 2027, the cash ISA allowance for under-65s drops from £20,000 to £12,000. The stocks and shares ISA allowance remains at £20,000. The 2026/27 tax year is the last in which both partners can put a combined £40,000 into cash ISAs. If maximising cash ISA sheltering is part of your plan, this year is the time to do it.

The Additional Permitted Subscription (APS): When a spouse or civil partner dies, the surviving partner inherits a one-off ISA allowance equal to the value of the deceased's ISA at the date of death. This allows the money to stay sheltered in a tax-free wrapper even though it passes to a new owner. The APS must be claimed within three years of the date of death or 180 days after the administration of the estate is complete. Cohabiting partners who are not married or in a civil partnership do not have access to this rule — the ISA loses its tax-free status on death without the APS protection.

No-Gain-No-Loss Asset Transfers

One of the most powerful and underused advantages of being married or in a civil partnership is the ability to transfer investment assets between partners without triggering a capital gains tax event.

One of the most valuable benefits for married couples is the ability to transfer assets between one another on a 'no gain, no loss' basis. This means you can move shares or property to your partner without triggering an immediate Capital Gains Tax bill.

This matters because each individual has a CGT annual exempt amount of £3,000 per year (2026/27). A couple therefore has a combined exempt amount of £6,000. If one partner has already used their own £3,000 exemption through selling investments in the same tax year, they can transfer additional assets to the other partner — who transfers them to the receiving partner at the original acquisition cost, not the current market value — and that partner can then sell them using their own unused CGT exemption.

A worked example: James holds shares worth £30,000 that he originally bought for £24,000 — a gain of £6,000. He has already realised £3,000 in gains this tax year from other sales. If he sells the shares himself, £3,000 of the gain exceeds his remaining exemption and is taxable at 18% (basic rate) or 24% (higher rate). Instead, he transfers half the shares to his wife Emma. Emma's acquisition cost is £12,000 (half the original cost), and when she sells her half for £15,000, her gain is £3,000 — exactly within her unused exemption. No CGT for either partner.

The no-gain-no-loss rule applies to transfers of any capital asset between spouses and civil partners who are living together — not just investments. It also applies to property (other than the main residence in some circumstances), business assets, and other capital assets.

Bed and ISA across both allowances: Each partner can use their own annual ISA allowance independently. A couple can each sell assets held outside an ISA (crystallising gains up to their CGT exemption if needed), and use the proceeds to purchase the same assets inside their respective ISAs — sheltering the same investment permanently from future tax. This doubles the annual ISA sheltering capacity compared to a single individual.

Pension Contribution Strategies for Couples

Pension contributions offer 20–45% tax relief depending on your tax band. Managing contributions as a couple rather than individually can significantly improve the household's total after-tax pension wealth.

Contribute to the lower earner's pension. Where one partner has used up their own annual allowance, they can also pay into their other half's pension, so long as their partner has the allowance to spare. A non-earning partner can receive pension contributions of up to £2,880 per year net, which the government tops up to £3,600 through basic rate tax relief — even with no earnings. This keeps a non-working partner's pension growing and builds their NI record through continued pension savings.

The higher earner's pension is not always the most efficient vehicle for household wealth. Concentrating all additional pension contributions into the higher earner's pension maximises tax relief on contributions but creates an imbalanced household pension position. If the higher earner dies first or the relationship ends, the lower earner may be left with inadequate retirement savings. A balanced approach — both partners building their own pension pots to adequate levels — is usually preferable to pure tax optimisation.

Salary sacrifice benefits both partners. If either partner has access to salary sacrifice through their employer, using it maximises the net contribution to their pension. The employer's NI saving (currently 15% of the sacrificed amount) is sometimes passed on to the employee as additional pension contribution — check your employer's scheme terms.

The personal pension for the non-earner. A non-earning spouse or civil partner can contribute up to £3,600 gross per year to a personal pension and receive basic rate tax relief, even with no income. The net cost is £2,880 per year for £3,600 in the pension. Over a decade, this adds £36,000 to the pension pot at a cost of £28,800 — entirely from a household perspective, since the other partner funds the contribution from joint resources.

Review pension nominations jointly. Pensions pass according to your expression of wishes or nomination form — not your will. Ensure both partners have up-to-date nominations that reflect the household's current intentions, particularly given the April 2027 IHT change that brings unspent pension pots into the taxable estate. Anyone who is married should check their pension death benefit nomination, as after this rule change it might be best for many couples' IHT purposes to stipulate that the pension is paid in total to your spouse when you die, rather than any portion left to children or other family members.

Income Splitting: Reducing the Household Tax Bill

The UK income tax system taxes individuals, not households. But there are legitimate ways for couples to arrange income-producing assets so that more of the household's total income falls to the lower-rate taxpayer, reducing the overall bill.

Transferring savings to the lower-rate partner. Interest on savings is taxable at each individual's marginal rate. A higher-rate taxpayer pays 40% on savings interest above their £500 Personal Savings Allowance. A basic-rate taxpayer pays 20% on interest above their £1,000 PSA. If savings are held entirely by the higher earner, the household pays more tax on the same interest than if the savings were split between partners.

Transferring savings from the higher earner to the lower earner — or holding them in joint names — shifts the tax liability to the lower rate. Between spouses and civil partners, this transfer does not trigger any tax charge.

Rental income from jointly owned property. If you own a buy-to-let property jointly, rental income is split between partners in proportion to ownership. If both partners own 50%, the income splits 50/50 and each pays tax at their own marginal rate. If one partner is a higher-rate taxpayer and the other is a basic-rate taxpayer, holding the property in equal joint names produces lower overall tax than holding it entirely in the higher earner's name.

Note: you cannot arbitrarily declare an unequal split of income between joint owners to HMRC unless the actual ownership reflects that split. HMRC presumes income from jointly held assets is split 50/50 for married couples — if you want a different split, you must own the property in different proportions (via a declaration of trust) and complete form 17 to notify HMRC.

Dividend income from a family business. If you run a limited company as a couple and both are shareholders, dividends can be split between partners — taxing each person at their own marginal rate. This is legitimate provided both partners have a genuine economic interest in the business. HMRC will scrutinise arrangements where a spouse holds shares purely as a tax-reduction device without genuine participation in or contribution to the business.

The Personal Allowance: Each partner has a Personal Allowance of £12,570. If one partner has income below £12,570 and the other has income significantly above it, there is unused Personal Allowance on one side of the household. Transferring income-producing assets to the lower-income partner uses their otherwise wasted allowance.

The Marriage Allowance — Revisited in Context

The Marriage Allowance has its own dedicated article on this site, but in the context of couple financial planning it is worth covering the basics and the positioning.

If one spouse has earnings below the basic rate income tax band, they can transfer £1,260 of their personal allowance to their higher-earning spouse or civil partner. This can trim their overall tax bill by up to £252 in a tax year.

The eligibility conditions: the lower earner must have income below £12,570 (the Personal Allowance) and the higher earner must be a basic-rate taxpayer — earning between £12,571 and £50,270. If the higher earner is a 40% taxpayer, the Marriage Allowance does not apply.

The claim is made by the lower earner at gov.uk/marriage-allowance and can be backdated up to four years (to 2022/23 in the current window). A full four-year backdated claim is worth £1,008 as a lump sum, plus £252 per year going forward.

In the context of a broader couple financial plan, the Marriage Allowance is typically the smallest-value item — £252 per year is worthwhile but not transformative. The ISA doubling, asset transfer, and pension strategies above are generally worth significantly more.

Capital Gains Tax Planning as a Couple

The CGT annual exempt amount is £3,000 per person per year (2026/27). This was £12,300 as recently as 2022/23 — the cuts since then have significantly reduced the opportunity for straightforward planning, but the couple's combined exemption of £6,000 is still worth using.

Couples who are married or in a civil partnership can transfer investments between one another tax free, which effectively doubles the CGT exemption to £6,000.

Beyond the annual exemption, couples have two other CGT-planning levers:

Timing of sales across tax years. Each partner's £3,000 exemption resets annually on 6 April. Splitting a sale across two tax years — selling half before 5 April and half after 6 April — can use two years of exemption for one asset. Combined with both partners using their exemptions, a couple could shelter £12,000 of gains from CGT by carefully timing a sale across a year-end boundary.

The main residence exemption. The primary private residence (PPR) exemption exempts gains on your main home from CGT, subject to rules about periods of absence and letting. For couples, only one property can be the main residence at any given time — but the definition of which property qualifies can be elected between properties you genuinely use as a residence. If you have two properties you genuinely use as residences, a formal election within two years of acquiring the second property can be valuable. Take advice before making this election.

CGT rates for 2026/27: 18% on residential property for basic rate taxpayers (24% for higher rate), 10% on other assets for basic rate taxpayers (20% for higher rate). These rates apply to gains above the annual exempt amount.

Inheritance Tax: Where Marriage Really Matters

The IHT advantages of marriage are among the most significant in UK tax law.

When you add all of these allowances together (£325,000 + £325,000 + £175,000 + £175,000), married couples can theoretically pass on an estate worth £1 million to their children without any tax being due.

The mechanism:

• Spousal exemption: Everything left to a spouse or civil partner is completely exempt from IHT, regardless of value.
• Transferable nil-rate band: If the first spouse to die leaves their entire estate to the survivor, their unused nil-rate band (£325,000) transfers to the survivor's estate. When the survivor dies, their estate benefits from a combined nil-rate band of £650,000.
• Transferable residence nil-rate band: The same applies to the residence nil-rate band (£175,000), giving a combined maximum of £350,000.

From April 2027, pension pots enter the IHT net. The spousal exemption still applies to pension wealth passing between spouses — so if you die and your pension passes to your spouse, no IHT applies. If it then passes from your spouse to children, it is included in the surviving spouse's estate. Review pension nominations to ensure they reflect this.

Cohabiting Couples: What You Are Missing

There are legal, financial and tax privileges you could be giving up by not saying 'I do'. For couples who live together without being married or in a civil partnership, the following advantages are not available:

• No spousal exemption from IHT
• No transferable nil-rate band or residence nil-rate band
• No no-gain-no-loss CGT transfers
• No Marriage Allowance
• No APS (Additional Permitted Subscription) for inherited ISAs
• No automatic right to a partner's pension on death (nominations matter)
• No automatic right to inherit intestate (assets go to next of kin, not an unmarried partner)

For cohabiting couples, the priority actions are: make a will immediately (intestacy rules do not protect unmarried partners), ensure all pension nominations are current and name your partner explicitly, consider a cohabitation agreement that sets out how shared assets would be divided if you separate, and review life insurance arrangements to ensure the pay-out reaches the intended person.

If you are a cohabiting couple with significant shared assets — particularly property — seeking legal advice on how to structure ownership and protect each other is well worth the cost. The legal complexity of a relationship breakdown without a marriage framework can be significantly more damaging than the complexity of divorce.

Practical Steps: A Couple's Financial Checklist for 2026

Both ISA allowances: Have both partners used their £20,000 ISA allowance? If not, transfer funds to the partner who has spare allowance and fund their ISA before year end.

Marriage Allowance: Does one partner earn below £12,570 and the other between £12,571–£50,270? If not yet claimed, claim it and backdate to 2022/23 for up to £1,260 as a lump sum.

Asset transfers: Are investment assets concentrated in the higher earner's name? Review whether transferring some to the lower earner reduces the household's income tax and CGT exposure.

Pension nominations: Are both pension expressions of wishes current and correctly completed? Do they reflect your intentions given the April 2027 IHT change?

Non-earner pension contributions: Is the non-working or lower-earning partner receiving pension contributions? Even £2,880 per year net (£3,600 gross) builds the pension pot and NI record.

CGT planning: Have both partners' £3,000 annual CGT exemptions been used? Is there any asset that could be transferred to use the other partner's unused exemption?

Joint property ownership: If you own rental property jointly, is the ownership split the most tax-efficient given each partner's income tax band?

Wills and lasting powers of attorney: Do both partners have a current will and LPA? For cohabiting couples, this is urgent. For married couples, it is still essential — intestacy rules exist even in marriage and may not reflect your current wishes.

Frequently Asked Questions

Can we have a joint ISA? No. ISAs are individual accounts. But each partner has their own £20,000 allowance, giving a combined annual sheltering capacity of £40,000. You can fund each other's ISAs from joint resources without any tax charge between spouses.

Can I put money into my spouse's pension? Yes. You can contribute to your spouse's or civil partner's pension, provided they have unused annual allowance. The contribution receives tax relief at the basic rate — but your spouse cannot claim higher-rate relief on contributions you made, unless they have sufficient earnings to justify the contribution as their own.

Is it legal to transfer savings to a partner to save tax? Yes. Transfers of cash and assets between spouses and civil partners are tax-free. HMRC is aware of and accepts income-splitting between genuinely married couples as legitimate tax planning. The line is crossed if assets are transferred to a spouse purely on paper without genuine economic substance — for example, arranging dividend income from a family business in a spouse's name when they have no real involvement.

We are not married but have been together 15 years. Do we have the same rights as a married couple? No. There is no legal concept of "common law marriage" in England and Wales. Cohabiting couples have none of the tax advantages described above, no automatic right to inherit, and no automatic right to each other's pension. If you have significant shared assets and a long-term relationship, getting legal advice — and potentially getting married or entering a civil partnership — is worth considering.

The April 2027 pension IHT change affects us — what should we do? If you are married and one of you dies, the pension can pass to the surviving spouse free of IHT (spousal exemption). The IHT charge applies when it then passes from the survivor to children or other beneficiaries. Ensure pension nominations reflect this — nominating a spouse rather than children directly can defer IHT by one generation, giving the survivor time to draw down the pension efficiently. Take advice specific to your estate's size and structure.

For personalised advice on couple financial planning — including which strategies are most valuable for your specific income levels and asset position — Unbiased connects you with FCA-regulated independent financial advisers, many of whom offer a free initial consultation. For checking your own Marriage Allowance eligibility and backdating, visit gov.uk/marriage-allowance.

This article is for informational purposes only and does not constitute financial, tax, or legal advice. Tax rules, allowances, and rates are correct for 2026/27 as published by HMRC. Tax treatment depends on individual circumstances. Always consult a qualified adviser for advice specific to your situation.