HELP! PHOTOS DESATURATED WHEN SAVED!

I generally begin my editing in LR, then finish in PS before doing a final save as a JPEG. Note: I shoot in RAW and always save as a TIFF file up until I send to a client. Everything in LR and PS look great, and so do my TIFF files, however, my JPEGS are super desaturated for some reason! I had this problem once a few years ago when an update changed my color spaces and I didn't realize it, but everything appears to match this time so I am not sure what the deal is. Does anyone have any advice?? I am soooo frustrated and cannot figure this out for the life of me!