For residential properties, the Stamp Duty Land Tax rates in England and Northern Ireland are as follows:

• Up to £125,000: 0%
• Over £125,000 and up to £250,000: 2%
• Over £250,000 and up to £925,000: 5%
• Over £925,000 and up to £1.5 million: 10%
• Over £1.5 million: 12%

Based on these rates, here’s the breakdown for a £400,000 house:

• On the first £125,000: £0 (0% of £125,000)
• On the next £125,000 (from £125,001 to £250,000): £2,500 (2% of £125,000)
• On the remaining £150,000 (from £250,001 to £400,000): £7,500 (5% of £150,000)

Total SDLT = £0 + £2,500 + £7,500 = £10,000

So, the SDLT on a £400,000 house would be £10,000.

Please note that this calculation is for a standard residential property purchase and does not take into account any reliefs, refund or exemptions that may apply, such as first-time buyer relief or the 3% surcharge for additional properties. SDLT rates and thresholds may also differ in Scotland and Wales, as they have their own land transaction taxes.