You can find the most recent version of these forms here.

IRS Form 1040
Non-payroll contributions reported here. Contribution is an “above the line” contribution and lowers your Gross Income.
IRS Form W 2
This form is provided by the employer.  This form provides the total pre-tax contributions made to the HSA if a contribution is made by the employer. Contributions made pre-tax by employees through payroll deduction are also reported here.  Amounts are not included in taxable income.
IRS Form 1099-SA
Provided by institution holding the HSA money in December and mailed to the account holder in January.  This form documents HSA account distribution activity.
IRS Form 5489-SA
This form completed by the institution holding the HSA money is sent to account holders in January.  5489-SA accounts for contributions made to an HSA in the current calendar year.  For contributions made after January 1 and before April 15th, another 5489-SA will be sent out in May.
IRS Form 8889
Available on the IRS website, this form must be completed and attached to the account holder’s Form 1040 when filing their Federal Tax Return.