It revealed that seven out of ten of its clients admitted that the strain of poor finances had affected their relationship.
Matt Barlow, chief executive of Christians Against Poverty, said: "Stresses over money are widely acknowledged as a major contributor to marriage breakdown.
"Romantic gestures are great fun but if you know your money is in a mess and you want to do something lovely for that special person in your life, get your money straight.
"If you regard your marriage as a precious thing, you need it to safeguard it as much as you can from financial uncertainty.
"Once you are informed about what you have left to spend, you can plan for a romantic dinner and have the double enjoyment of knowing you can afford it."
CAP has 150 debt counselling centres across the UK. Last year it helped more than 19,000 start the journey from debt to full financial recovery and is currently handling more than £64 million of arrears.
Its CAP Money course, which teaches simple but effective money management skills, is running in 129 churches this month alone.
Erdington Elim Pentecostal Church, in Birmingham, is starting its course on February 14 and, despite the big date, is anticipating a full house.
Course leader Dave Lawson said: "We have quite a range of people, a single mum, some couples, all of whom are keen to get their finances straight and their bank accounts working hard for them.
"It may not be the obvious romantic occasion but certainly for our church, it is one way we can show our love and care for our local community particularly in the current economic climate."