ZURICH, Switzerland — Buying a second-hand luxury watch on Ebay should get easier next year as the online auction platform gets better at checking that only genuine timepieces go under the hammer.

"By the end of 2019, we look to have an entire suite of services available to all luxury watch sellers and buyers on the platform," James Hendy, in charge of Ebay's authentication service for luxury goods, told Reuters in a recent interview.

While new watch sales have grown more slowly, the used market has been boosted by younger consumers happy to buy online, prompting Cartier owner Richemont to buy second-hand platform Watchfinder.co.uk.

Hendy said Ebay's transaction volume of second-hand luxury watches would exceed $1 billion in 2018. This compares to volumes of around €1.3 billion expected at German rival Chrono24 by its co-chief executive and founder Tim Stracke.

Ebay allowed approved professional sellers, like Watchfinder or Watchbox, to list timepieces on Ebay with an "authenticity verified" tag in September by extending its Ebay Authenticate program from handbags to luxury watches.

I believe that in the next few years the primary and secondary market are going to come together.

And from the first quarter of 2019, Ebay will allow consumers to instantly sell their luxury watch on the site, adding authentication services to cover all consumer-to-consumer (C2C) transactions during the second half of the year.

Swiss luxury watch brands have long hesitated to sell online and used to look at platforms like Ebay or specialised websites Chrono24 or Chronext as a nuisance because watches which retailers find hard to sell often end up online at a discount.

However, Ebay is now looking at partnerships with luxury brands as it targets a market estimated to be worth around €17.6 billion ($20 billion) when jewellery is included, a recent report by Bain & Company said.

The used market has been boosted by younger consumers happy to shop online, prompting watch manufacturers like Richemont or Audemars Piguet to enter the market.

"I believe that in the next few years the primary and secondary market are going to come together," Hendy said, adding that brands working with Ebay would be able to engage with customers directly via its platform.

By Silke Koltrowitz; editor: Alexander Smith