Greater Manchester Passenger Transport Executive (GMPTE) is writing to 400,000 people who will soon be eligible for free travel on most local bus services in England.
People aged over 60 and disabled people can already travel for free after 9.30am on buses, trains and trams in Greater Manchester if they have a GMPTE travel pass.
But from 1 April next year, they will only be able to take advantage of the full range of free travel on offer - including free off-peak bus travel throughout England - if they have a new national 'smartcard' pass.
GMPTE is asking everyone who receives the letter to provide a passport-style photograph and confirm their details so they can be sent the new card in time for 1 April, when it replaces all current free travel passes.
Michael Renshaw, Interim Service Delivery Director at GMPTE, said: "We are working hard to make sure that the change to the new national smartcard pass runs as smoothly as possible.
"We are writing to some 400,000 people who we have identified are eligible for the new pass but we can't guarantee that we will reach everyone directly.
"With the numbers involved it's important that people complete their application forms as soon as possible so we can make sure that we get all the new passes ready in time."
Anyone eligible who does not receive a letter by December should call into a GMPTE Travelshop (at main bus stations across Greater Manchester) or call Traveline on 0871 200 2233 (calls cost 10p per minute from landlines, mobile and landline networks may charge additional tariff costs) and ask for an application form. Textphone users should ring 0870 241 2216.
People who become eligible for passes between now and the end of March should apply to GMPTE Travelshops or by post from Travel Concessions, Customer Services, GMPTE, PO Box 429, M60 1HX.