If you are looking at your W-2 you are not going to find "the employee only contributions to HSA."  All contributions to an HSA made through payroll are styled on the W-2 as "employer" contributions.  This in no way affects your income tax benefit.  ALL the money contributed into the HSA - money that is yours and completely under your control - has been deposited pre-tax.  That's the income tax benefit and somehow slicing and dicing that amount into "employer" and "employee" amounts affects nothing.

The contribution to the HSA should be reported in one of the "12" boxes, coded "W."

Tom Young