The hourly minimum wage for over-24s is going up by almost 5 percent - to 8-pounds-21 but council tax, prescriptions costs and many bills are also expected to increase for thousands of people.
It's claimed households will have to find an extra £240 on average over the next 12 months to cover the increased living costs.
Liam Purcell from Church Action on Poverty told Premier's News Hour: "It's good that people are getting more money if they're on the so-called national living wage but there is this growing problem of all of the other factors that are affecting people - rising prices on all sides.
He argued that the government's definition of a living wage was below many campaigners': "The government labelled the 'minimum wage' the 'living wage' a couple of years ago but it's actually not a living wage if it's not enough to live on.
"Our standards of living of what you can actually buy with that money have been dropping and stagnating."
He added that prices are often higher for poorer people, for example, being more likely to have a pre-payment meter and not pay bills by direct debit or facing higher rates of interest because of paying with borrowed money.
Purcell said that individuals were trapped but could be helped by society: "It's good that churches often take a lead on these things, churches are in a good position to lead the way - for instance [many] churches are already committed to paying a real living wage and churches can speak truth to power."
Stay up to date with the latest news stories from a Christian perspective. Sign up to our daily newsletter and receive more stories like this straight to your inbox every morning.