There are certain deadlines that you need to meet related to your Aadhaar to avoid pain in the coming year, 2018. However, the government has requested the Supreme Court to postpone the hearing on the legality of Aadhaar to next year, and has expressed its willingness to extend the Aadhaar linking deadlines with various services by three months to March 31, 2018.While the final decision regarding this is still pending in the apex court, here's the list of various deadlines set by the government regarding the 12-digit unique identity number.The government had earlier notified that income tax returns (ITR) filed after July 1, 2017 would be accepted only after a tax assessee linked his/her PAN with Aadhaar. However, many people faced difficulty in doing so even by the extended deadline for filing returns of Aug 5, 2017.One of the often cited reasons for inability to link was mismatch of PAN and Aadhaar details due to spelling and other errors. Therefore, the government has given a relaxation to individuals who have filed their ITRs on or before August 5, 2017 but have not linked their PAN with Aadhaar. The new deadline set by the government is now December 31, 2017. Individuals must link their PAN with Aadhaar by this date in order for their returns to be processed.Government has made it mandatory to link Aadhaar and PAN for every PAN holder (except certain categories exempted via notification dated May 11, 2017) by amending the income tax laws in the last Union budget.However, the above deadline is only for those filing income tax returns this year. If you are not required to file your ITR as per tax laws, i.e., your gross total income in a financial year is less than the exemption limit of Rs 2.5 lakh (for the FY 2017-18), then the last date to link your PAN with your Aadhaar is yet to be notified by the government.You are required to link your Aadhaar to bank accounts, credit cards, insurance policies, equity and mutual fund investments, small savings schemes like Public Provident Fund, Kisan Vikas Patra, National Savings Certificate, Sukanya Samriddhi Yojana and so on. You are also required to submit your Aadhaar details if you have taken a loan from a bank, housing finance company, or non-banking finance company.Government has asked banks, financial institutions, and intermediaries to ensure that all their customers are know-your-customer (KYC) compliant which, as per new rules, requires verification of their Aadhaar. An amendment has been made in the Prevention of Money Laundering Rules (Maintenance and Records), 2005 to this effect.As per the new rules, one has to mandatorily submit his/her Aadhaar and PAN details to be KYC-compliant. If this is not done before December 31, 2017, his/her account will become inoperable till the time the required details are submitted.While submitting these details, you are also required to undergo an authentication process to verify that the Aadhaar submitted by you is actually yours, as per the notified rules.The department of telecommunications (DoT), after the Supreme Court judgment on February 6, 2017, has asked telecom operators to re-verify all the existing mobile subscribers (pre-paid and post-paid) via Aadhaar-based e-KYC. It has also become mandatory to provide Aadhaar details while buying new mobile SIM connections.As per the Supreme Court order, the process of re-verification of all existing mobile subscribers must be completed by February 6, 2018.However, as per the directive issued by DoT in its circular dated March 23, 2017, it is not clear what will happen if Aadhaar details are not linked to a customer's mobile number by February 6, 2018. At the same time, the telecom companies, on their websites, are cautioning users that their mobile connection services might get restricted or their numbers might become inactive in case Aadhaar-based compliance is not done. There have been news reports that all unlinked mobile numbers will be deactivated after the deadline.Recently, government in the Supreme Court said that it has extended the deadline for mandatorily providing Aadhaar details in order to avail benefits of social schemes. The new extended deadline is now December 31, 2017. Earlier deadline for the same was September 30, 2017.Aadhaar details are required for various benefits such as availing subsidy on LPG cylinders, the Human Resource Development ministry's scholarship schemes, availing pensions and subsided ration under Public Distribution System scheme.