Proportional VAT (also called partial deduction) is the method for allocating input VAT when a business has both taxable and exempt sales. It ensures the VAT deduction matches the VAT Act and VAT liability .
What is proportional VAT?
When a business sells both items with deduction rights and items without, input VAT must be allocated proportionally. Proportional VAT is calculated by looking at the share of turnover that gives deduction rights, relative to total turnover.
Formula for proportional VAT
$$ \text{Deductible input VAT} = \text{Total input VAT} \times \frac{\text{Turnover with deduction right}}{\text{Total turnover}} $$
Practical example
- Total turnover: NOK 1,000,000
- Turnover with deduction right: NOK 600,000
- Input VAT on shared costs: NOK 50,000
Deduction: 50,000 × 600,000 / 1,000,000 = NOK 30,000
Remaining 20,000 is non-deductible.
Documentation and adjustments
- Keep a calculation showing basis amounts and the fraction used.
- Adjust the fraction annually if the mix of turnover changes.
- For large changes during the year, consider interim adjustments to avoid under/over-deduction.
Typical pitfalls
- Using last year’s fraction without updating for major business changes.
- Forgetting to exclude exempt turnover when computing the fraction.
- Not keeping documentation for tax audits.
Summary
Proportional VAT allocates input VAT based on the ratio of deductible turnover to total turnover. Calculate the fraction, document it, and adjust when your revenue mix changes to stay compliant and avoid penalties.