Nil-Rate Band Discretionary Trusts: Planning Guide

The nil-rate band discretionary trust (NRBDT) was for decades the standard estate planning tool for married couples. Before October 2007, the nil-rate band (NRB) on the first death was wasted if all assets passed to the surviving spouse under the spouse exemption. Placing assets equal to the NRB into a discretionary trust on the first death preserved the band. The introduction of the transferable nil-rate band (TNRB) largely replaced this need — but the NRBDT has not become redundant. It continues to serve important purposes in the right circumstances.

This guide covers the mechanics, the tax treatment (including 10-year anniversary charges and exit charges), loan trust arrangements, and the circumstances in which an NRBDT or its modern equivalents remain appropriate. It does not constitute legal or tax advice.

What Is a Nil-Rate Band Discretionary Trust?

A nil-rate band discretionary trust is simply a discretionary trust funded, on death, with assets up to the value of the settlor's available NRB — currently £325,000. Because the fund value does not exceed the NRB, no IHT is payable when assets are transferred into the trust (the entry charge is nil). The surviving spouse is typically included in the class of beneficiaries, along with children and grandchildren.

The discretionary nature of the trust means no beneficiary has a fixed entitlement. The trustees — usually the surviving spouse plus an independent trustee — can appoint income or capital to any beneficiary as they see fit.

Pre-2007 Planning: Why It Was Necessary

Before the Finance Act 2008 introduced the transferable nil-rate band (with retroactive effect from October 2007), both spouses' NRBs had to be used on death or they were lost. A will that left everything to the surviving spouse used the spouse exemption but wasted the NRB. The NRBDT solved this by directing assets up to the NRB into trust on the first death. On the second death, the full NRB was again available against the surviving spouse's estate.

For a couple dying in, say, 2006 with combined assets of £1 million, an NRBDT could save up to £114,000 in IHT (40% of the 2006/07 nil-rate band of £285,000). Solicitors routinely included NRBDTs in mirror wills. Millions of such trusts were created.

The Transferable Nil-Rate Band: Effect on NRBDTs

The TNRB allows any unused NRB on the first death to be transferred to the surviving spouse's estate. This means that if a spouse leaves everything to their partner (using the spouse exemption in full), the survivor may have up to £650,000 of NRB available on their own death.

For simple estates, the TNRB makes a new NRBDT unnecessary. However, several factors limit the TNRB's utility and preserve the relevance of the NRBDT:

• Multiple marriages: the TNRB can be claimed from only one deceased spouse. If a surviving spouse has been widowed twice, only one unused NRB can be transferred — the second is lost.
• Wealthy estates: the RNRB tapers away above £2 million. Planning using trusts rather than relying solely on the TNRB may produce better outcomes.
• Asset protection: the TNRB does not protect assets from care costs, divorce, or creditors of the children. An NRBDT on the first death protects the trust fund.
• Second marriages: where either spouse has children from a prior relationship, passing assets directly to the survivor risks those children being disinherited. A trust preserves flexibility.

The 10-Year Anniversary Charge

Discretionary trusts are subject to the "relevant property" regime under the Inheritance Tax Act 1984. This means:

Entry charge: where assets passing into the trust exceed the available NRB, IHT is charged at 20% on the excess. For an NRBDT funded at exactly the NRB, there is no entry charge.

10-year anniversary charge: on every 10th anniversary of the trust's creation, IHT is charged at an effective rate (up to 6%) on the value of the trust fund above the NRB. The calculation is:

1. Calculate the "hypothetical chargeable transfer" — the aggregate of the trust fund value and any related settlements.
2. Reduce by the NRB available at the 10-year date.
3. Apply the IHT rate of 20%.
4. Multiply by 30% to arrive at the effective rate (maximum 6%).
5. Apportion the effective rate over the quarter of the 10-year period during which assets were held.

Where the trust fund remains below the NRB at each anniversary, no 10-year charge arises. But if the fund grows significantly, charges accumulate.

Exit charge: when capital leaves the trust (by appointment or distribution to beneficiaries), a proportionate exit charge applies. The exit charge is a fraction of the 10-year charge, based on how many complete quarters have elapsed since the last 10-year anniversary.

Exit charges are typically modest — the maximum effective rate of 6% per 10-year period means exit charges are usually well under 1% of the trust fund — but they must be calculated and HMRC notified.

Loan Arrangements: A Common Variation

A common variant of the NRBDT involves a loan from the estate rather than an outright transfer. Under this arrangement:

1. The deceased's executors lend a sum equal to the NRB to the trustees of the NRBDT.
2. The loan is recorded in a promissory note or loan agreement.
3. The loan balance forms a liability of the trust and an asset of the estate (specifically, of the surviving spouse who inherits the estate net of the loan).
4. On the surviving spouse's death, the outstanding loan is deducted from their estate, reducing the IHT base.

The advantage of the loan approach is that no assets physically leave the estate. The surviving spouse retains access to the funds through the trust (as a discretionary beneficiary) while the loan balance depresses their taxable estate. The loan should carry interest to avoid HMRC treating it as a gift with reservation, although interest at a low rate may be acceptable in practice.

Critics note that HMRC has scrutinised loan trust arrangements where the loan balance is inflated artificially or where the trust is a sham. The arrangement must be commercially structured and genuinely independent.

Modern Use Cases

Despite the TNRB, NRBDTs remain appropriate in several situations:

Second Marriage Planning

Where one or both spouses have children from a previous relationship, an NRBDT on the first death ensures those children benefit from at least the NRB trust fund, regardless of what the surviving step-parent does with the rest of the estate.

Asset Protection

Assets held in an NRBDT are outside the surviving spouse's estate for the purpose of means-tested care fees. They are also generally outside the reach of the surviving spouse's creditors or a second divorce settlement. This protection is valuable for families where there is business or personal financial risk.

Property Subject to Mortgage

Where the main asset is a mortgaged home, funding an NRBDT requires liquidity — the trust cannot hold a share of a mortgaged property without complex arrangements. Advisers sometimes use a charge over the property rather than a transfer, though this creates its own complications on sale.

Pre-2007 Trusts: Should They Be Wound Up?

Many existing NRBDTs were created before October 2007 and are now at or approaching their 10-year anniversaries. Whether to continue them depends on:

• Whether periodic charges are likely (has the trust fund grown beyond the NRB?)
• Whether the asset protection rationale still applies
• Whether the surviving spouse still benefits or whether the trust can be wound up without adverse consequences

Winding up an NRBDT triggers an exit charge on any assets distributed. Trustees should model the charge before acting and compare it to the ongoing cost of administration.

Interaction with the Residence Nil-Rate Band

The RNRB adds up to £175,000 per person to the NRB where a qualifying residence is left to direct descendants. An NRBDT does not, in itself, qualify for the RNRB — assets in a discretionary trust do not pass "directly" to descendants. However, assets can be appointed out of the trust to qualifying beneficiaries during the trust's life, which may then qualify.

Where a couple is planning a new will, it is worth considering whether an NRBDT or a direct gift to children on the first death better preserves the RNRB. A flexible life interest trust (interest in possession trust for the surviving spouse) may achieve a better result than a discretionary trust in some circumstances.

How Global Investments Can Help

Global Investments advises on all aspects of trust-based estate planning, including whether an NRBDT is the right tool for your family's circumstances, how to structure it to avoid unnecessary periodic charges, and how it interacts with your wider IHT planning.

We work closely with specialist solicitors to draft trust deeds and to review existing NRBDTs created under wills. We model the expected 10-year and exit charges to help trustees understand the ongoing tax cost of the trust, and we advise on whether winding up or retaining an existing trust is in the beneficiaries' interests.

This guide is for general information only and does not constitute legal or tax advice. Inheritance tax rules are complex and subject to change. Individual circumstances differ significantly, and you should seek professional advice tailored to your situation. The value of investments and income from them can fall as well as rise.