Many couples are unaware of the financial differences between marriage and cohabitation until they begin thinking seriously about estate planning, retirement, or Inheritance Tax (IHT). By that stage, opportunities to plan efficiently may already have been missed.
Understanding the tax benefits of marriage
Married couples and civil partners benefit from a range of valuable tax reliefs that are simply not available to unmarried couples, regardless of how long they have lived together.
One of the most important advantages is the spouse exemption for Inheritance Tax. Assets passed between UK-resident spouses or civil partners in lifetime and on death are generally free from IHT, with no upper financial limit. There is also no minimum marriage duration required for this exemption to apply.
In contrast, unmarried partners may face a 40% IHT charge on inherited assets above the available thresholds.
Another key benefit is transferable tax allowances. Each individual has a £325,000 Inheritance Tax allowance (known as the Nil Rate Band), along with an additional £175,000 Residence Nil Rate Band in certain circumstances. Married couples and civil partners can usually transfer any unused allowances to each other.
This can potentially increase the combined IHT-free allowance to £1m on the second death.
Marriage and civil partnerships can also offer further tax efficiencies:
- A surviving spouse or civil partner can inherit their partner’s ISA allowance, preserving the tax-free status of savings
- Assets can be transferred between spouses or civil partners without triggering Capital Gains Tax
- Pension planning flexibility, including contributions for a non-earning partner with tax relief
- Potential entitlement to certain State Pension benefits.
These reliefs can play a crucial role in protecting family wealth over the long term.
Why timing can make a difference
It is common for couples to only discover these differences when reviewing their Wills or considering later-life planning.
In some cases, this late awareness can lead to short-notice marriages (sometimes referred to as ‘deathbed marriages’), often prompted by health concerns or urgent financial planning needs. While such decisions can secure important protections, they are frequently made under considerable pressure.
Planning earlier allows couples to consider their options carefully and structure their affairs in a way that fully reflects their wishes.
The value of proactive planning
Taking advice early provides clarity and control.
Couples who plan ahead can:
- Put Wills and estate plans in place with confidence
- Align pension nominations and asset structures
- Make full use of available tax allowances
- Avoid rushed decisions at already stressful times.
Effective planning is ultimately about certainty – giving you peace of mind that your assets will pass as intended, while minimising unnecessary tax exposure.
How TWM can help
At TWM, our Private Client team advises individuals and couples on estate planning, tax efficiency, and wealth protection.
Whether you are married, in a civil partnership, or considering formalising your relationship, early advice can make a meaningful difference to long-term financial outcomes.
To discuss your circumstances, please contact our Private Client team for an initial, no-obligation consultation. We’re here to help you plan for the future with confidence.