29 May 2026
For many couples, marriage or civil partnership is about commitment, family and building a future together. But alongside the personal significance, there can also be important legal and financial advantages that are often overlooked.
One of the biggest differences between married couples, civil partners and unmarried couples is the way the law treats them for tax and estate planning purposes.
Many people assume that living together for a long time creates the same legal protections as marriage. In reality, that is not the case, particularly when it comes to Inheritance Tax (IHT), pensions and passing assets after death.
Understanding these rules early can help couples make informed decisions and avoid unnecessary tax liabilities later on.
Inheritance Tax and the Spouse Exemption
One of the most valuable tax benefits available to married couples and civil partners is the spouse exemption for Inheritance Tax.
In most cases, assets passed between spouses or civil partners, whether during lifetime or on death, are exempt from IHT. There is generally no upper financial limit on this exemption where both parties are UK domiciled.
For unmarried couples, the position is very different. If one partner dies, assets left to the surviving partner may still be subject to Inheritance Tax at 40% above the available tax-free thresholds.
This can come as a surprise to couples who have lived together for many years but never formalised their relationship.
Transferable Tax Allowances
Married couples and civil partners can also benefit from transferable Inheritance Tax allowances.
Each individual currently has:
Where allowances are not fully used on the first death, they can usually be transferred to the surviving spouse or civil partner.
This means some couples may be able to pass on up to £1million free from Inheritance Tax, depending on their circumstances.
Without marriage or civil partnership, these transferable allowances are not available in the same way.
Other Tax Advantages
Marriage and civil partnership can also create other financial and tax planning opportunities, including:
These reliefs can make a significant difference when planning for retirement, succession and long-term financial security.
Why Early Planning Matters
Many couples only become aware of these differences when reviewing their Wills or considering later-life planning.
In some situations, concerns about ill health or Inheritance Tax can lead to couples making decisions under pressure. Planning ahead gives you more time to consider your options carefully and ensure your affairs are structured in a way that reflects your wishes.
Good estate planning is not simply about tax efficiency. It is about providing certainty, protecting loved ones and avoiding unnecessary stress for family members later on.
Keeping Wills and Estate Plans Up to Date
Marriage, civil partnership, divorce and separation can all affect existing Wills and estate planning arrangements.
It is important to review:
Keeping these documents updated helps ensure your wishes are carried out and can reduce the risk of disputes or unintended outcomes.
Getting the Right Advice
Every family’s circumstances are different, and tax rules can be complex.
Taking legal advice early can help you understand your options, make full use of available allowances and ensure your estate planning reflects your long-term goals.
Our Private Client team advises individuals and families across Dorset, including Bournemouth, Poole, Christchurch and Highcliffe, on Wills, estate planning, Inheritance Tax and wealth protection.
If you would like advice tailored to your circumstances, contact our team to arrange a confidential consultation. Call 01202 294411, or contact us via our website to arrange a confidential consultation: Contact Us AB Solicitors For Your Legal Needs
