If tax is due you need one. Apply online at gov.uk/paying-inheritance-tax at least 3 weeks before you plan to send the IHT400.
Tax paid after the end of the sixth month after the death carries interest.
Tax on unsold houses and land can be paid over 10 years. Interest is charged on the unpaid amount. If the property is sold, the rest is due at once.
Most banks, building societies and NS&I can pay the tax from the deceased's money before probate. We fill one IHT423 per account.
That is allowed if you have made every reasonable effort to value them. You must tell HMRC the exact values once you know them.
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