Bookshop.org, the online bookseller, started selling books in the U.K. on Monday and is already showing strong sales. "After shipping is accounted for, we sold £135,000 in the first 48 hours" said founder Andy Hunter.

Bookshop, which launched in the U.S. in January, partners with independent bookstore and affiliates, and markets itself as a solution for bookstores that don't have robust online operations to sell books to customers who might otherwise go to competitor's websites. Hunter says the Booksellers Association in the U.K. got in touch with him shortly after the U.S. launch to discuss the possibility of expansion. Unlike in the U.S., where the American Booksellers Association has offered stores a variety of options to sell books online, including IndieBound, the U.K.'s BA has no such program. The U.K. site was planned, organized and launched in a three-month window. "It was daunting," admitted Hunter, "but we are happy that we stretched ourselves and got it done."

As of Tuesday, 150 bookstores across the U.K. had signed up to be Bookshop affiliates. Distribution is through Gardners and shipping times are two to three days from order to delivery. "Discounts for books are a bit worse in the U.K., but when you include shipping, the price to buy a book from the site is approximately the same as what you would pay in a store," said Hunter.

Like in the U.S., money is returned to affiliates as follows: for all sales directly from a bookstore affiliate site, the bookstore earns 30% of list price (not sale price), with the remaining 70% going to pay the publisher, cost of fulfillment by the wholesaler, the discount, and the payment processor -- earning Bookshop no direct profit. For all non-bookstore affiliates, 10% of list goes to the affiliate, and a matching 10% goes to the profit pool. On those sales, Bookshopearns a 10% profit (i.e. the 30% profit margin is split three ways).

After the first two days sales, "we are returning £35,000 to bookstores," said Hunter, noting this accounts for sales through bookstore affiliates and money going to the profit pool.

Bookshop has grown quickly in the U.S. and has sold $42 million in books since the start of the year and is on track, said Hunter, to hit $50 million before the end of the year. According to its website, which offers a running ticker of sales, Bookshop has generated $7.7 million for indie bookstores. The company has added people too, growing from four employees at the start of the year to 19 today. The staff in the U.K. is led by Nicole Vanderbilt, a former v-p of Etsy, who is serving as managing director. She oversees a staff of three that will soon expand to seven.

As in the U.S., some indie booksellers have been way of Bookshop and expressed fear that the company might siphon off sales that might have gone directly to stores, a criticism Hunter has dismissed in the past by saying the site ultimately only serves to grow the market.

The launch in the U.K. was self-funded and Hunter said that 80% of the profits from the U.S. site are being used to fund international expansion. Unlike the U.S., where the ABA made a $100,000 investment in the launch of Bookshop for a 4% stake in the company, the BA in the U.K. has not invested and is only served in an advisory role.

Bookstore associations in other countries are also interested in Bookshop. "I have heard from France, Germany, Italy, Australia, Turkey, Brazil, and Chile," said Hunter, who said Spain and Portugal are the company's next priorities. "We have a great team working on it . The plan is to launch there in the spring, realistically, in April."