The increase is due to the halving of the tax-free bracket that the government implemented at the end of 2017. In 2017, interest on savings accounts was still exempt from withholding tax up to 1,880 euros. In 2018, the tax-free bracket was set at 960 euros. At a savings interest rate of 0.11 percent, EUR 872,727 was exempt from withholding tax.
Anyone who receives more interest than the tax-free bracket is taxed on the surplus at a withholding tax of 15 percent. The tax is collected in two ways. If a Belgian receives more interest at one bank than the exempt amount, the bank will immediately withhold the withholding tax. If someone collects less than the exempt amount each time from several banks separately, but exceeds the exemption in total, he must file a declaration.
3,518 Belgians filed a tax return for assessment year 2019 – which relates to the 2018 income. In this way, the tax authorities collected 3.2 million euros in withholding tax through the tax return. In 2018 this was still 1.8 million euros.