Check numbers or risk a big fine.

Tens of thousands of businesses have used new laws to stamp out cold callers.

It is less than three months since new legislation came into effect enabling limited companies and public limited companies to opt out of receiving sales calls.

And already over 100,000 business telephone numbers have been registered with the Corporate Telephone Preference Service. (CTPS)

They join the 5.7m residential numbers already registered, and the 1.6m fax numbers on the Fax Preference Service (FPS) list.

And companies need to be aware of the businesses choosing to opt out.

Whereas telemarketing to people at home tends to be done only by dedicated call-centres, almost every business, both large and small, makes calls to other businesses.

If anyone in your business makes unsolicited calls how do you make sure they don't call someone who has opted out? You risk a pounds 5,000 fine if you get this wrong.

Fortunately there is a simple solution - and it is free if you only make relatively small numbers of unsolicited calls.

The website www.NumberCheck.co.uk enables you to check numbers against the national Telephone Preference Service, CTPS and FPS lists of opted-out numbers.

Since the law came into effect three months ago, more than 10,000 people have used the NumberCheck website, checking hundreds of thousands of numbers and nearly 11pc of all the numbers checked have been registered on the TPS or FPS list.

So if you and your staff are not checking numbers before you make unsolicited calls, then about one in nine of all of the calls you make could result in an angry conversation at best, or a pounds 5,000 fine at worst.

The existing Telephone Preference Service legislation enabling individuals to opt out their telephone number from unsolicited calls was extended to cover business telephone numbers as of June 25.