What a bank accepts as proof of income
3–6 months of company account statements with client payments visible. A yearly PIT return (PIT-36, PIT-36L, PIT-28). A „no arrears" certificate from ZUS and the tax office (US). Sales invoices from the last 3 months. A contract with a recurring client, if you have one. Two of these documents together are much stronger than one alone.
Banks that actually work with this profile
mBank Biznes has the simplest process for one-person businesses after a year of trading — an investment or cash loan up to 200 000 PLN, RRSO 12–14% with a strong profile. ING for business and BNP Paribas have a comparable offer. PKO BP usually wants 24 months of trading, but pays back with competitive rates.
Licensed lenders for businesses under 12 months
Smartney and SuperGrosz accept one-person businesses after 6 months. RRSO 25–35%. Decision in a day. Sensible as a first door, not sensible as a long-term solution.
Flat-rate tax 8.5%, 12%, 15% — why filing helps
Being on the flat-rate or the standard scale is a positive signal to a bank. It means you report income, you leave an administrative trail, you exist in the system. If you've never filed and you're wondering whether to start, do it. Over 12 months of filed returns your loan options grow exponentially.