Direct Descendants Inheritance Tax UK: Who Qualifies for the RNRB? (2026)
The Residence Nil-Rate Band (RNRB) saves up to £70,000 in IHT per person — but only when the home passes to direct descendants. Qualifying: natural, adopted, and stepchildren; grandchildren; and (in limited circumstances) children-in-law. Not qualifying: siblings, unmarried partners, nephews/nieces, or homes placed in a discretionary trust.
| Beneficiary Type | Direct Descendant? | RNRB Applies? | Notes |
|---|---|---|---|
| Biological child | Yes | Yes | Core qualifying beneficiary |
| Adopted child (legally adopted) | Yes | Yes | Any legally adopted child |
| Stepchild (child of current/former spouse or CP) | Yes | Yes | No formal adoption needed |
| Foster child (fostered by deceased while under 18) | Yes | Yes | Only while in foster care |
| Grandchild (natural, adopted, step) | Yes | Yes | Same rules as children, next generation |
| Son-in-law / daughter-in-law (child still alive) | No | No | In-law not qualifying unless child predeceased |
| Son-in-law / daughter-in-law (child predeceased) | Yes | Yes | Qualifying only in this specific scenario |
| Unmarried partner of deceased | No | No | Not a direct descendant; no spousal exemption either |
| Sibling of deceased | No | No | Lateral relative, not lineal |
| Nephew / niece | No | No | Not a lineal descendant |
| Discretionary trust (children as objects) | No | LOST | Trust not treated as passing to descendants |
| Bare trust for named grandchild | Yes | Yes | Grandchild is beneficial owner |
| IPDI trust (spouse life interest; remainder to children) | Yes (via s8H IHTA) | Yes — on survivor's death | Standard spouse-protection structure |
RNRB: Residence Nil-Rate Band — s8D IHTA 1984. 'Lineal descendants' defined in s8K IHTA 1984. RNRB £175,000 per person (frozen to April 2030). RNRB taper: £1/£2 above £2m net estate; fully lost at £2.35m (single) / £2.7m (couple). Transferred RNRB: s8G IHTA 1984; claim IHT436. IPDI RNRB preservation: s8H IHTA 1984. Downsizing addition: s8FA-8FE IHTA 1984; claim form LD1 on IHT400. Discretionary trust: RNRB LOST — ss8D and 8K require 'closely inherited' by lineal descendant. Bare trust for named descendant: RNRB preserved. 18-25 trust (s71D IHTA): RNRB applies where parent died and direct descendant is beneficiary.
Direct Descendants and the RNRB: Complete Guide
Who counts as a 'direct descendant' for the RNRB?
The Residence Nil-Rate Band (RNRB — s8D IHTA 1984) requires the main residence (or a share of it) to pass to a 'lineal descendant' on or after the date of death. HMRC defines 'lineal descendants' for RNRB purposes in s8K IHTA 1984: (1) A child of the deceased — this includes natural (biological) children; adopted children (legally adopted under any adoption order); stepchildren (a child of the deceased's spouse or civil partner from a current or previous relationship); foster children who were fostered by the deceased at some point while under the age of 18; children who were under the guardianship of the deceased while under 18 (including those appointed under a special guardianship order); (2) A grandchild of the deceased — natural, adopted, or step-grandchildren (applying the same rules at each generation); (3) Great-grandchildren and any more remote lineal descendants — the chain continues indefinitely down the line; (4) Spouses and civil partners of lineal descendants — if a child of the deceased was married, and the deceased leaves the home to the child's spouse (son-in-law or daughter-in-law), this DOES qualify as a direct descendant IF: the child (direct descendant) predeceased the deceased and the home passes to the child's surviving spouse or civil partner. So a son-in-law or daughter-in-law qualifies ONLY in this specific scenario.
Who does NOT qualify as a direct descendant for the RNRB?
The RNRB is lost (home does not qualify) if it passes to non-direct-descendants: (1) Siblings of the deceased — a brother or sister is not a lineal descendant (they are lateral relatives); (2) Nephews and nieces — not lineal descendants; (3) Uncles, aunts, cousins — not lineal descendants; (4) Parents of the deceased — not lineal descendants (they are lineal ancestors); (5) Unmarried partners of the deceased — an unmarried partner (even if a long-term cohabitant) is NOT a lineal descendant; importantly, an unmarried partner does not have the spousal exemption either — a large estate left to an unmarried partner at death faces the full 40% IHT above NRB £325,000 AND no transferred NRB; (6) Children-in-law (sons-in-law, daughters-in-law) as the primary beneficiary — a son-in-law or daughter-in-law does NOT qualify UNLESS their spouse (the deceased's child) predeceased the deceased and the home passes to the surviving in-law as above; (7) Friends, non-relatives, charities — not lineal descendants (charities are IHT-exempt but not because of the RNRB); (8) Home passing to a discretionary trust — even if the only beneficiaries of the trust are the children or grandchildren, a home passing to a discretionary trust is NOT treated as passing to a direct descendant; the RNRB is LOST. This is the most common and costly mistake in pre-2017 wills that set up NRB discretionary trusts including the home.
Trusts and the RNRB — which trust types preserve it?
Whether the RNRB is preserved when the home passes via a trust depends entirely on the trust type: (1) Discretionary trust: RNRB LOST. Even with children as the only beneficiaries, placing the home in a discretionary trust means it is NOT treated as passing to direct descendants. The RNRB is forfeited — up to £70,000 per person in additional IHT. This is the most common issue with wills drafted before 2017 that used NRB discretionary trusts; (2) Bare trust (absolute trust) for a named direct descendant: RNRB PRESERVED. A bare trust where the beneficial owner is a named direct descendant (e.g. a grandchild) is treated as passing directly to that descendant; (3) Immediate Post-Death Interest (IPDI) trust (s49A IHTA 1984): RNRB PRESERVED in most structures. An IPDI gives a specific beneficiary a right to income immediately on death (e.g. surviving spouse as life tenant). On the life tenant's death, the trust property passes to the remainder beneficiaries. If: (a) the life tenant is the surviving spouse and the home is in the trust; (b) the remainder beneficiaries are direct descendants; then the RNRB can apply on the surviving spouse's death (s8H IHTA 1984 — 'qualifying residential interest' passing to a direct descendant via an IPDI). This is the standard RNRB-preserving structure in spouse-protection wills: IPDI for the survivor; remainder to children; (4) 18-25 trust (s71D IHTA 1984): can preserve RNRB in limited circumstances — only where the trust is for a beneficiary whose parent died (not grandparent-created). The RNRB applies where the home passes to such a trust for a direct descendant.
Stepchildren and the RNRB — the common confusion
Stepchildren are direct descendants for the RNRB — but only if they are the children of the deceased's current or former spouse or civil partner. The deceased need not have formally adopted the stepchild. Example: a man remarries; his wife has two children from her first marriage. On the man's death, if he leaves his home to his wife's two children (his stepchildren), those stepchildren are treated as his direct descendants for RNRB purposes. The RNRB applies. Common scenario where this matters: where the deceased has no biological children of their own but has stepchildren from the current or previous marriage. Without this rule, the RNRB would not apply and the home would not qualify. Stepgrandchildren: the same principle extends — the grandchildren of a spouse or civil partner (who are step-grandchildren of the deceased) also qualify as direct descendants. The rule follows the step-relationship through each generation. Note: this applies to the current or former spouse/civil partner — not to a cohabiting partner's children (who are not stepchildren unless the partner was a spouse or civil partner of the deceased).
Downsizing addition — claiming RNRB when the home is sold
If the deceased sold or downsized their home (or gave it away) after 8 July 2015, the RNRB may still be claimed via the 'downsizing addition' (s8FA-8FE IHTA 1984). The addition: where the deceased previously owned a qualifying residential property (the 'former home'), sold or downsized it, and the value of the estate includes other assets (cash, investments, etc.) that pass to direct descendants, the RNRB can be claimed against those other assets — up to the amount that would have been available on the former home. The 'lost RNRB' calculation: the amount of RNRB lost because the former home is not in the estate can be claimed as an addition to the RNRB, applied to other qualifying assets that pass to direct descendants. Example: the deceased downsized from a £700,000 home to a £350,000 home. The former home would have attracted a full £175,000 RNRB. The downsized home attracts RNRB on its value (£175,000 maximum). The 'downsizing addition' allows the RNRB to be claimed on a further £325,000 of other assets (or up to the maximum RNRB, whichever is smaller) that pass to direct descendants. The claim is made via the IHT400 and the LD1 form (Residence Nil-Rate Band — downsizing addition). The direct descendant requirement still applies: the other assets being set against the downsizing addition must pass to direct descendants.
Frequently Asked Questions
Who counts as a direct descendant for inheritance tax purposes?
For the Residence Nil-Rate Band (RNRB — s8D IHTA 1984), direct descendants (lineal descendants — s8K IHTA 1984) include: natural children; adopted children; stepchildren (child of the deceased's current or former spouse/civil partner); foster children (fostered by the deceased while under 18); grandchildren (and their children, and so on); and spouses/civil partners of any of the above IF the direct descendant has already died. Does NOT include: siblings, nephews/nieces, uncles/aunts, cousins, unmarried partners, children-in-law (as primary beneficiaries while the child is alive).
Is a stepchild a direct descendant for the RNRB?
Yes — a stepchild is a direct descendant for the RNRB (s8K IHTA 1984). A stepchild is defined as a child of the deceased's spouse or civil partner (current or former). No formal adoption is needed. Example: a woman's husband has two children from his first marriage. On her death, if she leaves the home to her stepchildren, they qualify as direct descendants and the RNRB applies. This includes step-grandchildren (grandchildren of a spouse or civil partner following the same generational rule).
Does a discretionary trust lose the RNRB?
Yes — if the home is placed in a discretionary trust under the will, the RNRB is lost. Even if the only beneficiaries of the discretionary trust are children or grandchildren, the home is not treated as passing 'directly' to a direct descendant (s8D IHTA 1984 requires the qualifying residential interest to 'closely inherit' — i.e. pass on death directly to a lineal descendant). A discretionary trust does not satisfy this requirement. The loss of the RNRB costs up to £70,000 per person (£175,000 × 40%). Pre-2017 wills with NRB discretionary trusts are the most common cause of this. The fix: update the will to remove the home from the discretionary trust structure.
Does a son-in-law or daughter-in-law count as a direct descendant?
Only in one specific scenario: if the deceased's child (the direct descendant) has already died before the deceased, and the home passes to the child's surviving spouse (the son-in-law or daughter-in-law) — then that spouse IS treated as a direct descendant for the RNRB (s8K IHTA 1984). In all other cases: a son-in-law or daughter-in-law (living child's spouse) is NOT a direct descendant. If the home is left to a son-in-law or daughter-in-law while the child is alive, the RNRB does not apply.
What is the downsizing addition for the RNRB?
The downsizing addition (s8FA-8FE IHTA 1984) allows the RNRB to be claimed against other estate assets (cash, investments, etc.) if the deceased sold or downsized their home after 8 July 2015. The addition equals the amount of RNRB that would have applied to the former home but is no longer available because the home is not in the estate. The other assets claimed against the downsizing addition must pass to direct descendants. Claimed via form LD1 on the IHT400. This prevents the RNRB being lost simply because the deceased sold the family home and moved to a smaller property or into care.
Make Sure Your Will Claims the RNRB
Leaving the home to children or grandchildren in the will is the simplest and most valuable IHT planning step available — saving up to £70,000 per person. WillSafe will kits for England and Wales are designed to claim the RNRB correctly. From £39.99.
View Will Kits from £39.99