What is mandatory to maintain books of account in the case of taxpayers who opted for a presumptive tax scheme?
A Business entity opting for a presumptive tax scheme under section 44AD, 44AE, 44BB, or​44BBB is required to maintain books of account if the following conditions are satisfied:

 (a) Businesses eligible for presumptive tax scheme under s​ection 44AD

 For resident individuals or HUFs: If the income of the assessee exceeds the maximum exemption limit and he has opted for the presumptive scheme in any of the last 5 previous years but does not opt for the same in the current year.

 For resident partnership firm: The taxpayer has opted for the scheme in any of the last 5 previous years but does not opt for the same in the current year.

 (b) Businesses eligible for presumptive tax scheme under Section 44AE

 If the taxpayer (engaged in plying, hiring, or leasing goods carriage) claims that the profits are lower than the deemed profits computed under section 44AE.

 (c) Businesses eligible for Presumptive Tax Scheme under Section 44BB

 If the taxpayer (non-resident assessee engaged in the exploration of mineral oil) claims that the profits are lower than the deemed profits computed under section 44BB.

 (d) Businesses eligible for Presumptive Tax Scheme under Section 44BBB

 If the taxpayer (a foreign company engaged in civil construction) claims that the profits are lower than the deemed profits computed under s​ection 44BBB.​