When it comes to finding synonyms for "suck up to," there are a number of options to choose from depending on the context and the level of formality required. Some possibilities might include "brown-nose," "kiss up to," "flatter," "ingratiate oneself with," or "curry favor with." Other options could include "pander to," "grovel," "fawn over," or "sycophantize," although these tend to carry a more negative connotation and may not be appropriate for all situations. Ultimately, the key is to select a synonym that accurately reflects the intended meaning of the phrase while also fitting the tone and style of the writing or speech in which it is being used.