New systems would remove anxiety and save many thousands of hours' toil "and let businesses get on and do what they do".
He said "the change that has allowed the change" was the upcoming IRD update of its 1992 computing infrastructure. It was built for PAYE but now handled GST, Working For Families, Student Loans, KiwiSaver and other programmes.
Development Group chairman Tenby Powell said thanks to IRD's receptiveness of the group's recommendations small businesses would no longer be asked to pay provisional tax when at their lowest ebb.
Hawke's Bay Chamber of Commerce CEO Wayne Walford said the tax change was the biggest of all Budget announcements.
"This is huge for small businesses, as provisional tax is the bane of small business owners' lives. Previously they had to guess how much money their business might make in the future and forward pay."
Xero managing director Anna Curzon said GST processes would be "enhanced" for small businesses to allow provisional tax returns at the same time as GST. "This will reduce compliance, time and effort for small business owners and align their provisional tax payment to their cash flow," she said.
NOW CEO Hamish White said small business was the engine of economic growth "and anything that makes small business easier has got to be a good thing for New Zealand's economy".