When the service is relaunched on Tuesday, users will be able to identify a number of changes.
The most noticeable of these will come in the shape of the new "My Business" section in myIR, which will allow business owners to file, pay and amend GST as well as fringe benefit tax and gaming machine duty.
A new provisional tax option, called AIM or the Accounting Income Method, has also been introduced this month, with the effect of ensuring that small businesses will only have to pay provisional tax when they are making a profit.
"We are building up a set of products that are all designed to make tax simpler," said James.
"AIM will be a cash flow game changer while the new "My Business" section brings more tax types online and all in the one place."
Almost 14,000 people have attended either online presentations or seminars around the country to preview the improvements.