Loans starting from £150,000 in waves one and two were previously only available on a semi-exclusive basis.
The lender does not stress test borrowers and says it is targeting landlords most other lenders want to avoid.
These include foreign nationals, first-time landlords and owners of multi-unit freehold blocks.
Mark Posniak (pictured), managing director of Octane Capital, said: “In recent months, we’ve been further fine-tuning it and putting systems in place to ensure we could continue to provide a high quality service for brokers at scale and now we’ve reached that point.
“Our buy-to-let loans are targeting a demographic that the vast majority of lenders actively avoid, with many of our borrowers to date having multiple non-standard circumstances.
“But this is where we believe we stand apart as a lender and we look forward to helping as many brokers as possible during 2021.”