The Sunday Times has announced Britain’s top 100 Best Companies to Work For in 2015.

Online insurance company Simply Business was named in the top spot for companies with 250 to 2,5000 employees, while restaurant chain TGI Friday’s was named as the Best Big Company To Work For, in a category that recognised businesses with more than 3,500 staff.

The awards were announced during a ceremony in London on February 26.

More than 1,050 businesses and organisations registered to take part in four surveys for the 15th annual rankings of businesses with a happy and motivated workforce.

All the scores are based on employee opinions, and each year the questionnaires are revised and updated to reflect current workplace concerns.

The Sunday Times Business Editor, Dominic O'Connell, said:

Congratulations to all the organisations who made this year's The Sunday Times Best Companies to Work For lists. The methods of data gathering and analysis that has been used  are widely acknowledged as the most extensive research into employee engagement carried out in this country. We are extremely proud that the release of these lists is now a highly anticipated event in the business calendar.

Companies with 50 to 250 staff are assessed in The Sunday Times 100 Best Small Companies to Work For list – that will be published across all digital platforms on Sunday March 8.

Public-sector bodies, charities and housing associations are recognised in 100 Best Not-for-Profit Organisations to Work For. This list will appear on The Sunday Times digital versions on Sunday March 15.