99designs, one of the world’s most prominent online crowdsourced design marketplaces, has launched a UK-focused portal as it looks to ramp up its international growth efforts.

The platform lets businesses source customized designs for logos, websites, t-shirts, and almost any kind of design work, by initiating projects in a global community of more than 140,000 designers across 192 countries.

The company expects its design contests, of which there have been more than 117,000 to date covering logo, stationery, website, app design and more, to surpass the 200,000 mark by year-end. 99designs provides a 1-to-1 invoicing system that enables designers and customers to work together, and offers a ready-made logo store stocked with more than 13,000 logos available for customization and sale ‘off the shelf’.

The company was founded in Melbourne, Australia, in 2008 and opened its San Francisco headquarters in 2010 — London will be the company’s launchpad for its European expansion. With the launch into the UK, 99designs hopes to tap into 65,000 freelance graphic designers, and says it expects to pay out somewhere in the region of £16m in cash to designers in 2012.

“Our plan places London at the forefront of our upcoming expansion into the UK and continental Europe,” said CEO Patrick Llewellyn. “The UK has been a significant market for 99designs from the very beginning in terms of the design talent and customer base we’ve attracted there. We’re looking forward to building a strong presence on the ground to help UK designers build their businesses, enable companies of all scope and size to source affordable high-quality graphic design work, and enhance and expand our services on all fronts.”

The UK is one of 99designs’ fastest-growing ‘major markets’ — the company has increased its monthly UK design contests 120% year over year, and it says it expects to accelerate this growth with more locally-focused marketing and outreach activities.

Crowdsourced design platforms such as 99designs have come in for criticism in the past, with segments of the design community arguing that it doesn’t promote quality work and is more like a Walmart – focusing on quantity over quality. Designers submit work based on a specification within a contest listing, but critics say that there’s no guarantee of payment (the client will pick only one design, which will eligible for payment) which can mean wasted time and resources.

However, there’s no denying 99designs’ phenomenal success. It says a new design is uploaded every 5 seconds and more than $30,000,000 has been paid out to its design community in 4 years. Indeed, last year we reported that WikiLeaks was crowdsourcing a new t-shirt design using 99designs, whilst Techmeme followed suit a week later as it sought a new logo design through the platform.

The company was co-founded by entrepreneurs Mark Harbottle and Matt Mickiewicz (SitePoint, Flippa), and is backed by Accel Partners and angel investors Michael Dearing (eBay, Harrison Metal), Dave Goldberg (Survey Monkey), Stewart Butterfield (Flickr, Tiny Speck) and Anthony Casalena (Squarespace). It now has a team of more than 50 staff across San Francisco, Melbourne and London.

99designs (UK)