No Medicare and OASDI withholdings?

[Asdf42]

I recently switched jobs (same state) and checking at my paystubs I was shocked to see a huge difference in withholdings. 

Federal Withholding, State Tax - CA and CA SDI - CASDI seems to be alright and they increased as expected given the new tax bracket.

However, before I had 0 deductions for Medicare and OASDI, now I am seeing huge amounts there (Over $15k/yr) that I can't match anywhere before. Notice I am already matching all Federal, State and CASDI.

[lstone19]

Medicare and Social Security deductions are required by all employers (with some exceptions such as the federal government). Social Security up to the annual maximum and Medicare on all wages (if you overpay Social Security due to multiple employers, you get it back on your tax return). So you'd need to ask the old employer why they weren't withholding Social Security and Medicare.