"Be in for a treat" is a common phrase used to describe a situation where someone is about to experience something delightful or exciting. If you want to express this idea using different words, you can say "get ready for something wonderful," "prepare for an enjoyable experience," "anticipate a pleasurable outcome," or "expect a delightful surprise." Other synonyms that convey a similar meaning include "in for a good time," "about to be pleasantly surprised," "set for a treat," and "liable to enjoy something." No matter which words you choose to use, they all express the idea that something good is about to happen, and you should be excited about it!