The town beat off London boroughs and large towns and cities to get to the top slot. Windsor and Maidenhead has only 60.7 per cent of its older population in work. Buckinghamshire has 67.3 per cent of older people in work.
Rafiq Chohan, head of economic development, equalities and diversity at Slough BC, said: 'It is a well known fact that Slough is a great place to do business, and we benefit from high employment rates across all ages.
'A company with a mixture of ages will benefit from the experience gained from the older people along with the energy and dynamism of new younger employees.
'It's not true that when you get to 40 you are over the hill, and the success of Slough's companies - many of them FTSE 100 - is based on the knowledge and skills of its older employees.'
Derek Cyer, commissioner for social inclusion, said: 'I'm really pleased that companies across Slough value their older employees, they provide a vital contribution to the success of Slough's economy.
'And Slough Borough Council is leading by example with a high proportion of staff - 29 per cent - being over 50.'