Nigeria has hunted down 700,000 firms that have never paid taxes. The country with a population of about 180 million, slipped into recession in August for the first time in more than 20 years.
It is now seeking to find new revenue sources to compensate for low oil prices.
But it is an uphill task trying to get Nigerians to pay their taxes, considering that 80% the workforce is employed in the informal sector.
Tunde Fowler, executive chairman of the Federal Inland Revenue Service (Firs), said the aim was to bring the total number of registered individuals to 20 million by the end of the year:
"We have been able to add about 700,000 companies and we expect to add about 10 million individuals across the nation [by December]." , the Reuters news agency quotes its tax chief as saying.
He told Reuters there were plans to twin tougher enforcement with a waiver on interest and penalties for the period 2012-2015:
“We will give them a 45-day window to come forward and register and that will make them eligible for that waiver.
A lot of people who are not in the tax net are a bit jittery or afraid to come and register, thinking that we might go back two or three years and the amounts might be considerable."