HSA contributions and 415 compensation

[30Rock]

Are employee and employer contributions to an HSA grossed up for 415 plan compensation purposes?  I am not too familiar how contributions to these arrangements affect plan compensation. It looks like they can be run through the cafeteria plan - if so then I assume they would be considered Section 125 pre-tax amounts and then gross up the 415 compensation? Another way to set up an HSA is like an IRA and then take the deduction on your 1040. In this way, I assume the compensation is also included as 415 compensation in the employee's 401(k) plan?  If an employer wants to exclude them, I think they have to be excluded under the plan compensation definition in the document?

 

Any suggestions to assist me would be greatly appreciated!