Blemain Finance (part of Together) and Kensington Mortgages were the most complained about mortgage companies, according to the Financial Conduct Authority (FCA).

The regulator’s latest data release covering the second half of 2017 showed that Blemain received 43.1 and Kensington 41.1 complaints per 1,000 outstanding balances.

Charter Court Financial Services, which has the Precise Mortgages brand (33.9) and NRAM (31.9) were the next most complained about firms.

Using this method of analysis the mortgage lending market remains one of the most complained about sectors covered by the regulator.

Per 1,000 outstanding balances, the home finance sector received 9.6 complaints, up from 9.5 in the first half of the year.

By comparison, insurance and pure protection (8.3 per 1,000) and banks and credit cards (4.6) were the next most complained about sectors.

Overall the FCA received 3.76 million complaints during the second half of 2017 – up 427,032 from the previous six months.

Excluding Payment Protection Insurance (PPI) the number of complaints received by firms was 2.21 million, around 13,000 fewer than the previous six months.

After PPI, the next most complained about products were current accounts, with 509,047 complaints and then credit cards with 314,586 complaints.

Complaints about (PPI) rose by 40% to 1.55 million, the highest level of complaints about PPI for more than four years.

In January 2018 firms paid out £415.8m in redress to customers who complained about payment protection insurance (PPI).

This is the highest figure since March 2016 and takes the amount paid since January 2011 to £30bn.