Unison says that despite being accredited counsellors supporting patients with complicated mental health problems, the staff are still receiving trainee rates of pay.
The 20 counsellors staged initial walkouts in May and June. They have also been taking action short of strikes, refusing to offer any new high-intensity therapy.
Their employer, the charity Norfolk and Waveney Mind, is refusing to resolve the dispute, the union says.
Unison general secretary Christina McAnea said: ‘NHS counsellors support some of the most vulnerable people in society. Locally, they've been offering high-intensity therapy for years. Charity bosses should be ashamed that they're paying trainee rates for such crucial services.
‘It's time the employer paid up and ended this dispute. Then workers could get back to what they do best – helping vulnerable patients.'
Cameron Matthews, Unison Eastern regional organiser, added: ‘A well-known charity and NHS contractor such as Mind should not be exploiting frontline workers in this way. All staff want is proper recognition and fair pay for the work they do.'
In response, Norfolk and Waveney Mind, said: ‘We respect the right of our colleagues to be heard, but are disappointed that industrial action is continuing, particularly given the significant steps we have taken to recognise and invest in our counselling workforce.
‘Norfolk and Waveney Mind has engaged openly and consistently with staff and their representatives, and we remain committed to constructive dialogue. In 2024, we undertook a detailed review of counsellors' roles and responsibilities through an independent and evidence-based job evaluation process. This resulted in a substantial average pay increase for our counsellors in September 2024, an outcome that reflected the importance of their work, not a response to industrial action.
‘We remain focused on ensuring that local people across Norfolk and Waveney continue to receive the support they need. The NHS Norfolk and Waveney Talking Therapies service will continue to operate and we are taking all reasonable steps to minimise any disruption to the service users who rely on us. All other Norfolk and Waveney Mind services remain unaffected.'