Viagogo.com is offering tickets for up to £253 each. Its price includes a £31 booking fee. Getmein.com is charging up to £243 each, including a "processing fee" of £36 and £9 postage. Ticketlister.com is quoting up to £196.50 - £145, plus transaction fees of £43.50 and £8 postage. Tickets are also fetching £250 per pair on eBay.
RHS director general Sue Biggs urged gardeners not to buy tickets from touts, and warned online buyers they would be denied entry if their tickets turned out to be fakes.
The RHS originally charged £45 for all-day passes, £25 for afternoon entry and £19 for the morning. All the tickets went by May 6, 18 days before the show opens to the public on May 24.
"RHS Chelsea tickets have now sold out, so can I please ask people to not spend extortionate money via touts on tickets that may not be authentic and risk being refused entry."
Although reselling legitimate tickets online is legal, RHS spokesman Phil McCann said that they would be checking websites and working closely with police.