Hemel Stags will join Championship One in 2013, the Rugby Football League have announced.
The Stags will line up with Northampton and two other clubs from outside the game's traditional heartland in making the step up to semi-professional level.
"This is another exciting day for rugby league as we work tirelessly to grow and develop the sport," said RFL chief operating officer Ralph Rimmer.
"As with Northampton, this means further geographic expansion for Championship One and fits with our strategy to widen the sport's catchment area and increase the number of rugby league players involved.
"Hemel have a long and proud history and have played at the highest level of the community game for a number of years."
Chairman Bob Brown, the club's founder, said: "From the day in April 1981 when we kicked off as a pub team in borrowed shirts, we have been determined to grow the sport in Hemel Hempstead.
"Two decades of playing in non-professional national leagues have prepared us for the demands of Championship One.
"A long-term commitment to facilities and youth development has paid dividends and has made the Stags one of the leading sports clubs in the region.
"We had the team but not the facilities in place in 1998 when we unsuccessfully applied to join the Northern Ford Premiership.
"The one-year lead time we now have to prepare will ensure that we will be ready both on and off the field in 2013."