UPDATE 1-No concert, but Ticketmaster keeps processing fee

* Ticketmaster defends processing as labor intensive

* Lawmaker says rationale for charge is unclear (Adds lawmaker comment in paragraphs 8-9)

WASHINGTON, April 17 (Reuters) - A Washington, D.C. concert featuring jazz pianist Dave Brubeck has been canceled but fans were told by Ticketmaster (TKTM.O) that they will not get all their money back.

An email announcing the canceled April 18 concert offered to let Brubeck fans use the tickets for a future show, although no date for that show was given.

Fans will not automatically be given a refund but must send a letter requesting the money by May 5 and the original processing fee they paid will not be returned. "The $5.10 per order processing fee and any UPS delivery charges are nonrefundable," said the email from Ticketmaster.

Ticketmaster, which has said it would merge with the world's largest concert promoting company Live Nation (LYV.N), was besieged by complaints earlier this year when fans of Bruce Springsteen who signed on to Ticketmaster to buy concert tickets were told they had sold out within minutes. They were instead directed to the reseller TicketsNow which had considerably more expensive tickets.

Ticketmaster blamed that problem on a computer glitch.

Hannah Kampf, a spokesperson for Ticketmaster, said that Brubeck fans would get back what they paid for the ticket for the concert, but that processing the ticket twice -- once to sell it and once to refund it -- was labor intensive.

"From my standpoint, I think that that's pretty standard when there's labor involved," she said.