Senta, the holding company of corporate hospitality and social event organiser Event Vision La Dolce Vita, will be added, as will Philip Talbot Productions (PTP), specialists in award ceremony design and production.
As part of the agreement Elevation, which launched last year, could pay up to £9m for the two companies.
"PTP is in the middle of the field in which we operate. Both the skills and equipment resources are entirely relevant to our work, creating great synergy," said Elevation chief executive Ric Yerbury.
"Event Vision La Dolce Vita creates top-end hospitality and has enormous potential for growth. We are already looking to expand La Dolce Vita products worldwide, building on the events that take place in the UK and New York now."
Yerbury added: "We are in discussions with other businesses. We're in a fortunate position to be able to make acquisitions quickly and continue to receive enquiries from companies."