Analysis of the FCA's latest opened complaints data found organisations in the banking and credit card sector received an average of 15,360 complaints over six months.
The average amount consumers borrow to pay for insurance premiums has risen by 26% over the past year, according to research from Premium Credit.
Credit cards stayed popular for short-term, unsecured borrowing, but only 36% of card holders said they would use them again for a big purchase.
For big purchases like home improvements, 28% looked to borrow between £10,000 and £25,000.
A new study by Pepper Money reveals that 26% of UK homeowners have missed a credit card payment in the past two years, with growing reliance on short-term borrowing putting financial stability at risk.
One in four UK mortgage holders rely on credit to meet payments, as mortgage arrears and possessions surge, StepChange reports.
71% of customers use some form of credit to fund cover, which is virtually unchanged from the 72% recorded in last year.
817,400 mortgaged households plan to take on debt, with 26% intending to finance home improvements.
Nationwide's April Spending Report reveals a 25% rise in debt repayments as consumers manage cost of living pressures.
In response one broker said: “Many of the borrowers I deal with have far more unsecured debt these days, often worrying amounts, which they are then looking to consolidate into their mortgage.”