Visit the nearest Aadhaar Enrolment/Update Centre
Carry your Aadhaar card and a valid identity proof
Fill out the Aadhaar Update/Correction Form
Enter the new mobile number in the form
Submit the form at the centre
Complete biometric verification if asked
Pay the applicable update fee
Collect the update acknowledgement slip with the URN
Use the URN to track the update status
Wait for the mobile number update to be processed
Note that mobile number update cannot be done online without biometric verification