The 27-year-old represented England Under-19s and scored 72 on his Glamorgan debut in 2006.
Wright, who has a batting average of 27.08 from 89 first-class matches, struggled to secure a first-team place.
"It has not been an easy decision, but I'm very excited to be starting a fresh challenge," he said.
Glamorgan chief executive Hugh Morris said: "Ben has been a true professional and will be missed both in the dressing room and with his skills on the field."

Ms Wood blamed the Conservatives in particular for claiming the SNP posed a threat to the future of the UK.
She claimed "progressive" parties like hers were offering a "collaborative" alternative to "combative" politics.
"This election presents an opportunity for harmonious co-existence between our nations," she said.
Ms Wood's comments followed Conservative claims that Labour dependence on support from the SNP to form a government after the election on 7 May would threaten the break-up of the UK.
Campaigning in south Wales on Monday, she said: "The parties advocating progressive, inclusive non-partisan cooperation in this election are not those who claim to cherish the political union above all others, but the national parties of Wales and Scotland.
"Along with the Greens in England, our parties have provided people across these islands with a collaborative alternative to the traditional combative Westminster politics."
Ms Wood added that she had received "hundreds" of supportive messages from people in England following the televised debates.

Seonaid, 21, won the 50m rifle three positions event with an accumulated score of 458.5.
Elder sister Jennifer, 26, won gold in the 50m rifle prone event on Monday.
She also featured in Thursday's three positions event, as Great Britain took overall team gold.
Jennifer finished fifth in the event as the McIntosh sisters, alongside shooter Katie Gleeson, finished in first place with their combined scores.
Ukraine were second, with France taking third.

The Weston-super-Mare Bemusement park was originally due to go to the so-called "Jungle" camp in Calais, France.
It has now been donated to Aid Box Convoy, which is taking it to a smaller camp where conditions are said to be "horrendous".
The fixtures and fittings will be used to build shelters and cooking stations.
More than 150,000 people visited the Dismaland exhibition at the disused Tropicana site in Weston.
Now, eight vehicles and 20 volunteers will take leftovers from Bristol to the camp in northern France. They are also taking with them five tonnes of donated firewood and some 300 aid boxes containing food, toiletries and cooking equipment.
Co-founder of Aid Box Convoy, Imogen McIntosh, said the camp only has basic sanitation and has "grown from 400 people three weeks ago to more than 1,000, with families turning up every day".
Ms McIntosh said Dismaland organisers changed their mind about sending the camp to Calais when they heard there were other camps in France which hadn't received any aid.
She added: "It has all been taken down now and we are left with huge sheets of wood which we can use to build the shelters.
Dismaland is also sending a team of chippies and builders out to the camp, who will be creating any structures that we need with the materials."
The group has also been supported by Bristol-based Arcadia Spectacular - known for its festival fire-breathing spider - which has donated a vehicle and trailer.
"People have been so fantastic, it's been such a brilliant response and so much better than we could ever have imagined," added Ms McIntosh.
Glamorgan batsman Ben Wright will retire at the end of the season to pursue a career with a metal manufacturer.
[NEXT_CONCEPT]
Plaid Cymru leader Leanne Wood has accused rival parties of "dangerous and divisive rhetoric" in a "desperate" attempt to win votes.
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Scotland's Seonaid McIntosh has won gold at the European Shooting Championships in Baku, Azerbaijan, three days after her sister Jennifer achieved the same feat.
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The dismantled Dismaland theme park is on its way to a refugee camp in France after Banksy donated it to a group of Bristol volunteers.