Dixons Carphone, which owns the stores, said all standalone UK Carphone Warehouse stores will close, with those in Currys PCWorld shops to remain open.
It said today’s announcement is an essential next step in the firm’s turnaround of its mobile phone business, which will make a £90m loss this year, to profitability.
It said customers are changing the way they buy mobile devices and connectivity, replacing their handsets less often and buying them separately or as part of more flexible bundles.
Alex Baldock, Group Chief Executive, said: “Customers are changing how they buy technology, and Dixons Carphone must change with them.
“Clearly, with unsustainable losses of £90m expected this year, Mobile is currently holding back the whole business.
“There’s never an easy time for an announcement like this, but the turbulent times ahead only underline the importance of acting now.
“I don’t underestimate how upsetting this news will be for our colleagues, and we’ll treat everyone with honesty, respect and care.
“We want to keep as many of our Carphone Warehouse colleagues as we can, and expect to find new roles for almost 40 per cent of those affected. We’re working hard to look after those colleagues we can’t find new roles for, financially and otherwise.
“But though this is by far the toughest decision we’ve had to make, it is necessary. We must follow our customers. They want help with all technology, all in one place, and this trend is only going to accelerate in a more connected 5G world.
“So customers are increasingly heading, not just to our large and growing online business, but into our big stores, where they can find all the experts and tech they need. But they can’t find all this in the small mobile-only stores that are one twentieth of the size; they’re visiting these less and these stores are losing more money as a result.
“That’s why we’re committed to our more than 300 big stores around the UK, why we’re investing tens of millions of pounds in them.”