Income tax return is submitted to Income Tax department whereas ROC returns are filed with Ministry of Corporate Affairs (MCA) with whom the company is registered. It is mandatory to file the prescribed ROC forms and other returns on annual basis.

Form MGT 7 is used to file Annual Return. The due date is May 30.
Form AOC 4 is used to file Annual Accounts. The due date is 180 days from end of Financial Year(FY).

Form MGT 7 is used to file Annual Return. The due date is 60 days from conclusion of Annual General Meeting(AGM).
Form AOC 4 is used to file Annual Accounts. The due date is 30 days from end of Financial Year(FY).

For LLPs, the due date of return filing is 60 days from end of financial year i.e 31st May of the assessment year. For form 8 (Statement of solvency) the due date is 30th October.

If the LLP annual return form is not filed within due date, then a penalty of Rs.100 per day is applicable until the default continues. There is no limit on the maximum penalty amount and hence the amount increases over time.
In case of company, the penalty amount depends upon the nominal share capital and period of delay.

LLP form 11 needs to be signed with digital signature of any one designated partner.
In case of company, the annual return form has to be signed with the digital signature of the director or the company secretary in practice (as the case may be).