Kent based Darenth Valley Building Services (DVBS) has been granted a Royal Warrant by Her Majesty the Queen for building services and maintenance engineering.
There are only around 850 Royal Warrant holders across the world and companies can only apply after working for the Royal household for at least five years.
DVBS was established in Crockenhill by Terry and Wendy Divers in October 2000. Clients include E&J Gallo Winery European headquarters, Continental Tyres and Hasbro.
Terry said: 'When I opened the letter informing us that we had been granted our Royal Warrant it was the best Christmas present I could ever have received - it was an incredibly emotional time in the office, and a credit to all our staff.'
Terry has been working within the building services industry for more than 30 years and worked on the steering committee with the Heating and Ventilating Contractors Association which produced the Cleanliness of Ventilation Systems Document TR/17.