Compliance calendarHard deadline
Statutory deadline
CMP-08 due date
CMP-08 is the composition scheme's quarterly statement and payment; GSTR-4 is the annual return that follows the year.
CMP-08
Quarterly statement and tax payment under the composition scheme
Falls due
18th of the month after each quarter (January, April, July, October)
Applies if
you are registered under the GST composition scheme
Extensions happen. These are the statutory dates. The CBIC and CBDT extend them often enough that you should confirm against the official portal before relying on one — particularly in the first year of a change. Cortex warns you ahead of the statutory date, which is the one you can plan around.
Stop tracking this by hand.
Cortex shows the statutory dates that apply to you on your dashboard and compliance calendar, ahead of the day, alongside your receivables, your payables and the MSME 45-day clock. Upload a Tally, Vyapar or Busy export and it reads your numbers as they come.
General information, not tax advice. Your own dates depend on your registration, turnover and constitution — check with your CA.