For alfalfa and maize silages, the use of silage preparations (bacterial, chemical and combinations of bacterial and chemical) was tested between 2018 and 2022. Not only were the types of preparations compared, but in some cases their recommended application doses. The results show that, under ideal conditions, the differences between the control without silage preparation and the other variants with silage preparations and between them are mostly erased. In that case, the use of silage products is mainly a guarantee that for some reason (mostly technological or managerial) the fermentation process does not proceed as it should. Under adverse conditions, the positive effect of using a suitable product and a suitable application dose is usually significant. Then its use is inevitable, especially from the point of view of reducing losses.