Lawmakers have proposed the value-added tax (VAT) be increased by one percentage point and the additional revenue used only on education and health care.
They forecast the increase would bring another 60-70 billion to state coffers each year.
The National Legislative Assembly (NLA) also advocated variable VAT rates based on the necessity of each product or service category.
The VAT rate was set at 10% but the effective rate has been 7% since 1997. Each government issues an announcement each year to keep the 7% rate for political or economic reasons.
The NLA on Thursday considered a tax restructuring report proposed by its economic, finance and fiscal panel.
Revenue collection has failed to meet targets since 2013 after Thailand cut its tariffs in line with obligations under the World Trade Organization and free trade agreements, according to the report.
Therefore, the panel proposed measures to help boost revenue.
Apart from the VAT hike, the report suggested the Revenue Department study whether a company with offices or branches should separate the accounts of these offices based on locations so they could pay local taxes. A consolidated account should not be accepted for tax calculations, the report said.
As well, the panel recommended the Finance Minister study and impose the windfall tax on landowners or businesses benefiting from land price increases and developments in locations where state-financed mass transit or rail lines pass.
The Revenue Department should also find a way to plug the loophole in e-commerce with servers abroad as payments made by Thais and profits made by vendors are not taxed. Multinational companies may need to have offices in Thailand for the purpose.
The report also wants a change to the current duty exemption on imported goods with value under 1,500 baht apiece, viewing it as a loophole.
The NLA approved the report without a vote and will send it to the cabinet for further consideration.