Dennis was acquired by private equity house Exponent three years ago.
The business spun off its automotive brands and ecommerce sites into a separate venture, Autovia, earlier this year.
Future is acquiring the £104m turnover Dennis division that includes The Week UK and US, The Week Junior UK and US, MoneyWeek, Kiplinger, Science & Nature, Computer Active, PC Pro, Minecraft World, Coach and ITPro.
Some 56% of sales at the operation come from the US, and 75% of sales are subscription based. The Week family of titles and Science & Nature will add over 700,000 subscribers to the Future business.
The operation had EBITDA of £20m last year.
Future CEO Zillah Byng-Thorne, said the Dennis buy was part of the group’s longstanding “US first” mindset and would boost its subscription know-how.
"I am delighted to announce the acquisition of a high-quality portfolio of Dennis' trusted brands that will accelerate our strategy, enhance our content capabilities and bring additional geographical and vertical revenue diversification, whilst materially increasing the proportion of recurring revenues across the group,” she said.
Dennis CEO James Tye said the business had been on “an incredible growth journey” in its three years under Exponent.
“This is a testament to the talented team at Dennis who have helped make all of this happen. We look forward to working with the team at Future to continue growing the reach, influence and value of all our key brands and businesses."
The deal is subject to a number of conditions before completion, which is expected to be on 1 October.
Future will pay around £300m in cash for Dennis, funded by its debt facility which was increased to £600m last month. As part of the deal structure Exponent will pay Future a minimum of £8m, and up to £10m, within 12 months.
Future has already identified £5m in cost synergies.
Exponent has retained four titles that are not part of the deal: Viz, Fortean Times, Cyclist and Expert Reviews.
The £340m turnover Future business acquired TI Media in October 2019.
Future, TI and Dennis work with a number of print suppliers including William Gibbons and Walstead Group.
