Improvement
Expert Insights system rolled out to all 48 calculators
Every calculator now provides contextual tips, warnings, and opportunities based on your results. Insights are included in PDF exports with a mandatory financial advice disclaimer.
Rate Updates and Changelog
Every HMRC rate change, new calculator launch, and improvement is logged here. We verify all rates against official GOV.UK sources before updating our tools.
Improvement
Branded PDF exports with QR codes and watermark
PDF downloads now include the full-colour WhatsUK logo, a QR code linking back to the calculator, a subtle brand watermark, and a professional layout with HMRC verification badge.
New Tool
Self Assessment Calculator launched
New calculator covering income tax on self-employed profits, Class 4 NI, student loan repayments, and payments on account for 2026/27.
Source: HMRC Self AssessmentRate Update
Employer NI rate updated to 15% (April 2026 change)
Employer National Insurance increased from 13.8% to 15% and the secondary threshold dropped from £9,100 to £5,000. All employer cost calculators updated.
Source: gov.uk NI ratesRate Update
Stamp duty thresholds reverted to pre-2022 levels
The temporary SDLT threshold increase ended. The nil-rate band returned to £125,000 (from £250,000) and first-time buyer relief threshold to £300,000 (from £425,000). Additional property surcharge increased to 5%.
Source: HMRC SDLT ratesRate Update
Corporation Tax marginal relief calculations verified
Main rate remains 25% for profits over £250,000. Small profits rate of 19% for profits under £50,000 confirmed. Marginal relief fraction 3/200 verified against HMRC guidance.
Source: HMRC Corporation Tax ratesRate Update
Student loan Plan 5 threshold added
Plan 5 (for loans taken out from September 2023) added to all calculators with student loan support. Threshold: £25,000 at 9%.
Source: SLC repayment thresholdsRate Update
2026/27 income tax and NI rates applied across all calculators
Personal allowance frozen at £12,570. Basic rate 20% (£12,571 to £50,270), Higher rate 40% (£50,271 to £125,140), Additional rate 45% (over £125,140). Employee NI: 8% and 2%.
Source: HMRC Income Tax ratesWant to know more about how we verify our rates?