Interest in Possession Trusts: Uses, Tax Treatment, and International Planning

What an interest in possession trust is

An interest in possession (IIP) trust is a specific form of trust where at least one beneficiary — the "life tenant" — has an immediate and legally enforceable right to receive the income from the trust as it arises. The trustees are legally required to pay the income to the life tenant; they cannot accumulate it or redirect it to other beneficiaries (without the life tenant's consent or specific trust powers).

The capital of the trust — the underlying investments, property, or other assets — passes to the "remaindermen" when the life interest ends. Typically, the life interest ends on the life tenant's death, so the trust is effectively a life interest with a remainder gift.

This structure was historically used to benefit a surviving spouse (who receives the trust income for life) while protecting the capital for children (who receive it on the spouse's death). It remains in widespread use for estate planning, asset protection, and international planning purposes.

IHT treatment: the critical 2006 divide

Before 22 March 2006, the IHT treatment of IIP trusts was relatively simple: the trust assets were treated as forming part of the life tenant's estate for IHT purposes (the "transparency" rule). On the life tenant's death, IHT was assessed on the trust assets as if they were part of the personal estate. Correspondingly, the life tenant could not make lifetime transfers of the trust assets without creating PETs or CLTs.

The Finance Act 2006 fundamentally changed the IHT treatment of IIP trusts created by lifetime transfer from that date onwards. New lifetime IIP trusts are generally treated as "relevant property" trusts — the same regime that applies to discretionary trusts. This means:

A transfer into the trust on creation is immediately a chargeable lifetime transfer (CLT), subject to IHT at 20% on the amount above the available NRB.

A 10-year anniversary charge (the periodic charge) applies at up to 6% of the trust's value in excess of the available NRB.

Exit charges apply when assets leave the trust before the 10-year anniversary.

The post-2006 lifetime IIP trust is therefore substantially less tax-efficient than its pre-2006 predecessor. In practice, most professional advisers now prefer discretionary trusts for new lifetime arrangements, where the tax treatment is at least no worse and the flexibility is greater.

Will trusts: the continuing transparency exception

The major exception to the post-2006 regime is the "immediate post-death interest" (IPDI) trust — an IIP trust created by will or on intestacy. If the trust comes into existence on the testator's death, and the life tenant's interest begins immediately (rather than after a postponed period), the old transparency rules continue to apply. The trust assets form part of the life tenant's estate for IHT.

This is the primary route by which new IIP trusts are still created for estate planning purposes: via will trusts benefiting a surviving spouse. The spouse receives income for life (and typically has the right to occupy any trust property); on the spouse's death, the assets pass to children. The assets are in the spouse's estate for IHT, but the spouse exemption means no IHT arises on the first death; the assets are assessed on the second death, using the NRB and RNRB of both spouses.

Bereaved minor's trusts and 18-25 trusts created by will also retain favourable IHT treatment.

Income tax treatment in the trust

The trustees are responsible for completing a tax return and paying income tax on the trust's income. The standard trust rate applies to non-savings income (20% up to the basic rate band of the trust, with no higher rate tax paid by the trust — unlike discretionary trusts which pay at 45% above the standard rate threshold).

The life tenant is then taxed on that income as if they had received it personally. They receive a tax credit for the income tax already paid by the trustees. If the life tenant is a basic-rate taxpayer, they will receive a repayment of any excess tax paid by the trust. If the life tenant is an additional-rate taxpayer, they will have further tax to pay.

This treatment means the life tenant's personal circumstances — their marginal rate, their personal allowance, their savings and dividend allowances — are relevant to the overall tax burden. A life tenant who is non-UK-resident and exempt from UK income tax on trust income (subject to treaty provisions) may have particular planning opportunities here.

CGT treatment

An IIP trust has its own CGT position. The trustees pay CGT on gains realised within the trust at the trust rate — currently 24% on both residential and other chargeable assets (trustees do not have a basic-rate band, so the lower 18% rate available to some individuals does not apply). The annual exempt amount for trusts is currently £1,500 (reduced from £6,150 in recent years and now one-half of the £3,000 individual annual exempt amount).

When the trust comes to an end — typically on the life tenant's death — the trustees are treated as disposing of the trust assets at market value, and may have CGT to pay on the gain since the assets were settled into the trust. However, no CGT is payable on a "deemed disposal" at the life tenant's death on assets that are within the life tenant's estate for IHT purposes under the transparency rule. This is one of the benefits of the IPDI regime — IHT transparency carries with it CGT relief on the termination event.

Holdover relief is available in certain circumstances when assets are appointed from the trust to beneficiaries: the gain is "held over" into the recipient's base cost, deferring rather than eliminating the CGT.

International uses of IIP trusts

Offshore IIP trusts — established with trustees in Jersey, Isle of Man, Guernsey, or similar jurisdictions — are used by UK expatriates and internationally mobile families for several purposes.

A UK long-term resident who settles assets into an offshore trust does not escape UK IHT on those assets — the assets remain within the relevant property regime and may be within the settlor's estate depending on the trust type. However, individuals who settle non-UK assets before becoming a UK long-term resident (the residence-based test that replaced domicile for IHT from 6 April 2025) can use excluded property trusts that sit outside the UK IHT net — a separate planning area, now subject to the post-April 2025 restrictions linking excluded-property status to the settlor's long-term resident status.

For an IIP trust, the offshore structure may offer investment flexibility (access to a wider range of asset classes via an offshore trustee), professional administration (regulated trustee companies with investment expertise), and privacy (offshore trust registers are not publicly accessible in the same way as some UK trust records, though the Trust Registration Service requirements extend to relevant offshore trusts with UK connections).

UK-resident beneficiaries of offshore IIP trusts — particularly beneficiaries whose income from the trust is matched against the trust's accumulated income and gains — need to take advice on the offshore trust matching rules (discussed in the Phantom Income guide).

Practical planning considerations

IIP trusts remain valuable where the life tenant's need for income is the primary planning objective and where the transparency rule applies (IPDI on death). The flexibility of a discretionary trust is generally superior for purely IHT-driven planning, but the IIP's forced income distribution can be an advantage where the life tenant genuinely needs the income and the trustees wish to be released from the discretion of accumulating or redirecting it.

Will drafting should be reviewed regularly as tax law changes. Existing trusts with IIP provisions — particularly those created before 2006 — may benefit from a structural review to assess whether the current IHT treatment is as expected and whether amendments are possible or desirable.

Tax treatment depends on individual circumstances and the dates on which trusts were created and amended. This guide is for information only. Always take specialist legal and tax advice before creating or amending a trust.

How Global Investments can help

Global Investments works with trustees, settlors, and beneficiaries of IIP trusts on the tax and investment management dimensions of trust planning. We can review the IHT status of existing trusts, model the income and CGT implications of different investment strategies within the trust, and coordinate with trust solicitors and accountants on structuring distributions. For internationally mobile clients, we advise on the offshore trust dimension. Contact our private client team to arrange a trust review.