There are described concentrated liquid formulations (a) comprising (a.sub.1) 1 to 80% by weight of a microbicidally active ingredient, (a.sub.2) 20 to 99% by weight of a mono- or dihydric alcohol or mixtures thereof, and concentrated liquid formulations (b) comprising (b.sub.1) 5.1 to 30% by weight of microbicidally active ingredient, (b.sub.2) 0 to 80% by weight of sulfonate, (b.sub.3) 1 to 60% by weight of a C.sub.1 -C.sub.11 monocarboxylic acid or of a C.sub.3 -C.sub.12 di- or -polycarboxylic acid; (b.sub.4) 0 to 90% by weight of a mono- or dihydric alcohol or mixtures thereof, and water to 100%, it always being necessary for one of the components (b.sub.2) or (b.sub.4) to be present. The formulations according to the invention are used as microbicidally active ingredient in cosmetic products, household articles or hand disinfectants, as preservatives in household articles and cosmetic products and as disinfectant and decontamination agent for textile fibre materials or the skin and hard surfaces.