Last month, the lender processed a record number of new deals.
Hitting the £1bn target was milestone in its five-year history said the firm.
The Cardiff-based company was acquired by specialist lender Pepper Money in October 2018.
Chief executive Sam Marshall (pictured) said: “When we started up the company we set out to become the biggest second charge lender in the UK, a target we achieved very quickly. Our acquisition by Pepper Money will enable us to continue to grow, and we look forward to further successes in the future.
“Despite some uncertainties in the lending market given the ongoing Brexit discussions, we have found the second charge market to be very buoyant.”
The number of new second charge mortgage deals taken out in July came to 2,656, according to data from the Finance & Leasing Association (FLA)
The figure represented an increase of 23 per cent on July 2018.
The value of that business has risen 17 per cent to £115m for July this year compared to the same month in 2018.