Humanists UK says the number of religious chaplains operating within the NHS is disproportionately high, given the proportion of people who do not have a faith - more than half according to Social Attitudes Survey data.
Director of public affairs and policy, Richy Thompson told The Observer newspaper: "Non-religious people want to meet someone who is like-minded and the data suggests religious chaplains don't generally visit non-religious people.
"Research shows that only around four-per-cent of visits by religious chaplains are to the non-religious."
Humanists UK believes current chaplain teams do not properly serve the non-religious, and the organisation has been fundraising in order to pay for and train so-called non-religious pastoral carers.
Amid a backdrop of NHS funding pressures, the number of NHS chaplaincy posts fell by 20-per-cent between 2010 and 2015 to 916, according to the Health and Social Care Information Centre.
Mr Thompson went on to say: "Often being able to speak to someone who shares your world view facilitates the ability to explore deep existential questions and enhance someone's wellbeing at a point of crisis."
In April, a humanist was chosen for the first time to lead an NHS chaplaincy team.
Lindsay van Dijk was appointed to the post at the Buckinghamshire Healthcare NHS Trust.
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