This is up from the monthly average of £4bn in the six months to February 2020.
The statistics also show that there were 99,000 mortgage approvals for house purchase in January, in line with the average of 100,000 since October 2020.
In addition, effective interest rates on new mortgage borrowing fell to 1.85% in the first month of the year.
That is in line with the rate in January 2020, and compares with a series low of 1.72% in August 2020.
The rate on the outstanding stock of mortgages fell to 2.09% which is a new series low.
David Whittaker, chief executive of Keystone Property Finance, said: “Today’s statistics show that the housing market remained resilient as the New Year kicked off, with demand for property continuing to rise as people take advantage of low interest rates and the stamp duty holiday.
Graduate recruitment has fallen and house prices are higher than ever
A generation is coming of age during the pandemic and it is set to leave long lasting scars on them, both emotionally and financially. While the former is much harder to pin down, the latter can be categorised and quantified.
Young people will face years of turmoil, long after the coronavirus crisis has abated. This will have a negative impact on their employment prospects, debt levels and housing dreams.
How long will young people suffer in the aftermath of Covid-19, and can they do anything about it?
Employment woe
Average asking prices started to drop in the past month and there are now well over 600,000 homes caught up in a completion log-jam ahead of the stamp duty holiday ending on 31 March.