The Portal of the General Department of Taxation for Foreign Providers (etaxvn.gdt.gov.vn) came online Monday for companies to declare their tax and track their payments.
Until now foreign companies were paying their taxes through a third party, but now they could pay directly, Nguyen Van Phung, head of the Large Enterprise Taxation Agency, said.
By filling in their details on the website, businesses could see how much they need to pay and bank account details, he said.
"Foreign [companies] can now pay tax at any time, even from an airplane".
Generally foreign firms are required to pay value-added tax and corporate income tax every quarter.
Phung said many foreign firms have been leaving their Vietnamese partners with the burden of their tax, he added.
There are at least 64 foreign service providers active in Vietnam, according to tax authorities.
Vietnam taxed cross-border platforms like Google and Facebook a total of VND5 trillion ($218.53 million) in 2018-21.
Authorities have been calling for properly taxing tech giants like Facebook and Google, pointing out they account for around 70 percent of the online advertisement market but evade taxes.