On 13 November 2015, three gunmen killed 90 people and injured hundreds at the Bataclan nightclub in Paris.
The Tim Parry Johnathan Ball Foundation for Peace will support survivors who have travelled back to the city.
There was a "long-term need" for this support, Terry O'Hara from the Warrington-based charity said.
The group, which operates the UK Survivors Assistance Network, said it would "be in and around the Bataclan providing support for any UK victims of terrorism that have attended and obviously being available for any others".
Mr O'Hara said memorials were important to help survivors come to terms with what they had witnessed.
"There's a long-term need - these people have become members of a club they didn't want to join and there's a feeling that these attacks are very rare but incredibly impacting on the people affected and psychological trauma is overwhelmingly the after-effect that people struggle to find help with," he said.
The foundation is named after two schoolboys killed when two IRA bombs exploded in Warrington on 20 March 1993.
Tim Parry was 12 and Johnathan Ball just three years old when they were killed by the blast in a busy shopping street the day before Mother's Day. More than 50 other people were injured.
A charity that helps people affected by terrorism is to offer support at events marking the first anniversary of the Bataclan attack in France.