Four secondary ticket-selling websites have agreed to be more transparent, following pressure from the Competition and Markets Authority (CMA).
The sites re-sell tickets to music, theatre or sporting events which have previously been bought by somebody else.
They have been criticised for charging high prices, and not always showing the original cost of the tickets.
But the sites have now promised to give consumers clearer information.
Stubhub, Seatwave, Viagogo and Get Me In said they would make the changes demanded by the CMA.
As a result consumers will be able to see:
- The original cost of any ticket
- Whether there are entry restrictions and restricted views
- Whether multiple bookings refer to seats that are next to each other
- What additional charges are involved
- A contact email address if things go wrong
Some high profile artists, including the Arctic Monkeys, Iron Maiden and the management of One Direction, had called for even tighter rules.
They, and many sporting bodies too, had wanted consumers to be given the names of the original ticket-buyers.
Viagogo, which is based in Switzerland, promised it would abide by the new restrictions.
"We are always happy to listen to recommendations about the way we display information on our website, and we will be making these changes in due course," said a spokeswoman.
Ticketmaster, which owns Get Me In and Seatwave, said it would also become more transparent, even though it says its websites were already "a safe and secure place for fans to buy and resell tickets".
The changes come ahead of new legal restrictions that will be placed on ticket-selling websites.
Under the Consumer Rights Bill, ticket sites which break the law could face fines of up to £5,000.
They will be required to report criminal activity, and to give all necessary information to ticket-buyers.
The bill was passed by parliament last month, but has not yet received royal assent.
In the meantime, the CMA said ticket-buyers will have much better information to help them.
"We also advise buyers to check carefully before they buy and only use those platforms which give them the information they need," said Nisha Arora, CMA senior director.