The phrase "cutting on" can mean different things depending on the context. However, antonyms for this phrase could vary from "adding to," "building up," "constructing," "developing," and "enhancing." These words imply a sense of growth, progress, and improvement. For example, a person could say: "Instead of cutting on my expenses, I plan on building up my savings." In this sentence, the antonym for "cutting on" is "building up." Similarly, in a business setting, instead of "cutting on" the budget, a company could focus on "developing" new projects or adding more value to their products or services.