Estate Planning for Couples UK (2026): Wills, IHT, LPAs, and Property for Married Couples and Civil Partners

A married couple or civil partnership has access to significant estate planning tools that are not available to cohabiting couples. The core priorities are: (1) MAKE VALID WILLS — BOTH PARTNERS: the most important step. Without a will, the intestacy rules apply — and while a surviving spouse/CP inherits the statutory legacy (£322,000 as at 2024/25) plus half the residue above that, the remainder goes to children. For larger estates or where there are children from a previous relationship, intestacy creates significant problems. Both partners should make wills simultaneously — 'mirror wills' that reflect each other's wishes; (2) LASTING POWERS OF ATTORNEY — BOTH TYPES: each partner needs both a Property and Financial Affairs LPA and a Health and Welfare LPA. If one partner loses mental capacity without an LPA, the other may be unable to: (a) access joint bank accounts (some banks block accounts immediately on notice of incapacity); (b) sell the family home; (c) make financial decisions. A Court of Protection deputyship (MCA 2005 s.16) is the costly, slow alternative; (3) IHT PLANNING — USE THE COMBINED EXEMPTIONS: married couples and civil partners have combined nil-rate bands of £650,000 (£325,000 × 2) plus combined residence nil-rate bands of £350,000 (£175,000 × 2) — a combined threshold of £1,000,000 for estates passing to children. Ensure both are claimed; (4) PROPERTY TITLE — REVIEW TENANCY: check whether the family home is held as joint tenants or tenants in common. For estate planning with property trusts or to protect each partner's share for children from previous relationships, converting to tenants in common is essential; (5) EXPRESSION OF WISHES FOR PENSIONS AND LIFE INSURANCE: nomination forms for pension death benefits and life insurance trusts should be kept up to date — they override the will for those assets.

The spousal IHT exemption and transferable nil-rate band (TNRB) are the two most powerful IHT tools available to married couples and civil partners: (1) THE SPOUSAL EXEMPTION (IHTA 1984 s.18): transfers between spouses and civil partners are ENTIRELY FREE OF IHT — during lifetime and on death. When the first spouse dies and leaves everything to the surviving spouse, no IHT is payable regardless of the size of the estate. The surviving spouse's estate grows to include the inherited assets; (2) THE TRANSFERABLE NIL-RATE BAND (TNRB) — IHTA 1984 s.8A (Finance Act 2008): when the first spouse dies and their nil-rate band (NRB) is not fully used (because assets passed to the surviving spouse free of IHT under the spousal exemption), the UNUSED PROPORTION of the NRB can be transferred to the surviving spouse's estate and added to the survivor's own NRB. Key points: (a) the TNRB is expressed as a PERCENTAGE of the NRB at the date of the survivor's death — not the actual value at the first death. If the first spouse died when the NRB was £250,000 and transferred 100%, the survivor's estate gets 100% of the NRB at the time of the second death (currently £325,000); (b) two spouses = TWO NRBs = combined £650,000; (c) a widow/widower who has been married twice may be able to transfer up to 100% of one unused NRB — the maximum is 100% transferred, capped at one transfer regardless of multiple marriages; (3) THE RESIDENCE NIL-RATE BAND (RNRB) — IHTA 1984 s.8D: each person has a RNRB of £175,000 (2026/27) where a qualifying residential interest passes to lineal descendants. The RNRB is also TRANSFERABLE between spouses on the same basis as the NRB. Combined RNRB for a couple = £350,000; (4) COMBINED THRESHOLD: for a couple with the family home and lineal descendants inheriting: NRB £325,000 + TNRB £325,000 + RNRB £175,000 + TRNRB £175,000 = £1,000,000 before IHT applies; (5) ESTATES ABOVE £2M — RNRB TAPERING: the RNRB tapers away by £1 for every £2 by which the estate exceeds £2,000,000. For very large estates, take specialist advice.

Mirror wills are COMPLEMENTARY WILLS made by two people (typically a couple) that reflect each other's provisions — each leaves everything to the other on first death, with the same ultimate beneficiaries (usually children) on the second death: (1) WHAT MIRROR WILLS TYPICALLY PROVIDE: (a) each partner leaves their estate to the other absolutely on first death; (b) if the other has already died, the estate passes to the children equally; (c) each partner appoints the other as sole executor, with the same substitute executors (usually children); (d) each will may include the same guardianship appointment for minor children; (2) ADVANTAGES: simple; inexpensive; ensures the surviving spouse is fully provided for; maximises use of TNRB by leaving everything to the surviving spouse; (3) THE CORE RISK — SURVIVOR CAN CHANGE THEIR WILL: mirror wills are TWO SEPARATE LEGAL DOCUMENTS — each partner can revoke or change their own will at any time, WITHOUT the knowledge or consent of the other. After the first death, the surviving spouse can make a completely new will, leaving everything to a new partner, their own children from a new relationship, or anyone else. The children of the first marriage may receive nothing; (4) MUTUAL WILLS — THE BINDING ALTERNATIVE: MUTUAL WILLS (distinct from mirror wills) are wills made under a legally binding agreement that neither party will revoke after the first death. They create a CONSTRUCTIVE TRUST over the estate on the second death. However: (a) mutual wills are inflexible and difficult to enforce; (b) they prevent any tax planning after the first death; (c) they are rarely appropriate unless the risk of the survivor changing their will is the primary concern; (5) PRACTICAL SOLUTION: most couples use mirror wills for simplicity, combined with a PROPERTY WILL TRUST (life interest trust) to protect the family home for children — so even if the survivor remarries and changes their general will, the trust share of the property passes to the children on the survivor's death regardless.

For most couples with estate planning objectives beyond simple survivorship, holding property as TENANTS IN COMMON (not joint tenants) is preferable: (1) JOINT TENANCY — DEFAULT BUT INFLEXIBLE: as joint tenants, the surviving partner automatically inherits the deceased's share of the property by survivorship — regardless of any will. This maximises the surviving partner's security but: (a) the deceased's share cannot be left to children (will has no effect on the joint tenancy interest); (b) the property will form part of the survivor's estate on their death — potentially fully subject to IHT if the survivor's estate is large; (c) there is no opportunity for a property will trust; (2) TENANTS IN COMMON — FLEXIBLE AND NECESSARY FOR TRUST PLANNING: as tenants in common, each partner owns a defined share (usually 50% each). The deceased partner's share can be: (a) left to the surviving spouse absolutely — simple and maximises spousal exemption; (b) left into a LIFE INTEREST TRUST (property will trust) — surviving spouse has the right to occupy the property for life, with the deceased's share ultimately passing to children. This protects against: (i) the surviving spouse remarrying and leaving the property to a new family; (ii) the family home being used entirely for care fees; (3) SEVERING THE JOINT TENANCY: if the property is currently held as joint tenants, sever it by written notice and register a Form A Restriction at HMLR; (4) UNEQUAL SHARES: couples who have contributed unequally to the property purchase price may wish to hold as tenants in common in unequal shares — reflecting their actual contributions. A Declaration of Trust (TR1 or separate document) records the beneficial shares and prevents future disputes; (5) SECOND MARRIAGES: where either or both partners have children from a previous relationship, tenants in common with a property will trust is almost always essential — to ensure each partner's share of the family home ultimately reaches their own children.

Couples in a second or subsequent relationship where one or both partners have children from a previous relationship face additional estate planning complexity: (1) THE CORE RISK — ACCIDENTAL DISINHERITANCE: if each partner leaves everything to the new spouse/partner, and the survivor then dies leaving everything to their own children, the first partner's children from the previous relationship may receive nothing. This is an extremely common family dispute scenario; (2) MIRROR WILLS ALONE ARE INSUFFICIENT: as discussed above, the surviving partner can revoke their will after the first death. The first partner's children have no legal claim to the estate under English law unless they are provided for in the survivor's will or an Inheritance Act 1975 claim applies; (3) PROPERTY WILL TRUST: at minimum, each partner should convert the family home from joint tenancy to tenants in common in 50% shares and make wills leaving their share into a LIFE INTEREST TRUST — giving the surviving spouse the right to live in the property for life, but ensuring that partner's 50% share ultimately passes to their own children; (4) INHERITANCE ACT 1975 CLAIMS BY CHILDREN: children (including adult children) of the first relationship can make a claim under the Inheritance (Provision for Family and Dependants) Act 1975 if they have been financially dependent on the deceased parent and reasonable financial provision has not been made. However, such claims are uncertain, expensive, and time-consuming; (5) LETTER OF WISHES: each partner should leave a detailed letter of wishes alongside their will, explaining their intentions for the benefit of both the surviving spouse and the children from the previous relationship — though a letter of wishes is not legally binding; (6) FINANCIAL AGREEMENT: in some cases, a formal agreement between the partners (sometimes called a 'post-nuptial agreement') can provide additional certainty — though the enforceability of post-nuptial agreements in England is not absolute; (7) ADVICE ESSENTIAL: blended family estate planning is one of the most complex areas of wills and trusts law. Both partners should take independent legal advice.