The invention relates to a cold-rolled flat steel product which, despite high strength values, has a high level of deformability characterized by a high elongation at break and a good hole expansion ratio λM. For this purpose the flat steel product is produced from a steel that is composed of (in % by weight) C: 0.12-0.19%, Mn: 1.5-2.5%, Si: >0.60-1.0%, Al: ≤0.1%, Cr: 0.2-0.6%, Ti: 0.05-0.15% with the remainder being iron and unavoidable impurities caused by the production process, and which comprises a perlite- and bainite-free structure having 4-20% by vol. martensite, 2-15% by vol. residual austenite, remainder ferrite, an elongation at break A80 of at least 15%, a tensile strength Rm of at least 880 MPa, a yield strength ReL of at least 550 MPa and a hole expansion ratio λM of more than 6%. The invention also relates to a method which easily enables production of a flat steel product according to the invention.