Year
Contribution Limit
(Single)
Contribution Limit
(Family)
Additional Catch-Up Contribution
(55 or older, Single and Family)
2017
$3,400
$6,750
$1,000
2016
$3,350
$6,750
$1,000

Open Deadline: April 15 of next year, no extension.
Fund Deadline: April 15 of next year, no extension.
Annual contribution limit may be affected by the number of months that you have an HDHP in a given tax year.
You cannot use HSA funds to pay for expenses incurred prior to opening the account.
Health Savings Accounts (HSA) must be established by the tax filing deadline (without extensions) for the tax year in which your qualifying contribution(s) will apply. 
Any eligible individual can contribute to an HSA.
For an employee’s HSA, the employee, the employee’s employer, or both may contribute to the employee’s HSA in the same year as long as the aggregate contributions are under the contribution limit.
Family members (or any other person) may also make contributions on behalf of an eligible individual.
Contributions must be made in cash.  Contributions of stock or other property are not allowed.
HSAs can be funded with rollovers or transfers from an Archer MSA.
A one-time qualified HSA funding distribution may be made from your Traditional or Roth IRA to your HSA.  The maximum amount depends on your type of coverage (single or family).  The distribution is not included in your income, is not tax deductible, and reduces the amount you can contribute to your HSA.
Limit on Contributions
The contribution amount to an HSA can depend on the type of HDHP coverage you have, your age and the date you become an eligible individual, and the date you cease to be an eligible individual.  
If you were, or were considered (under the last-month rule), an eligible individual for the entire year and did not change your type of coverage, you can contribute the full amount based on your coverage.
If you were not an eligible individual for the entire year or changed  your coverage during the year, your contribution limit is the greater of:
The limitation shown on the Line 3 Limitation Chart and Worksheet in the Instructions for Form 8889 
The maximum annual HSA contribution based on your HDHP coverage (single or family) on the first day of the last month of your tax year (usually Dec. 1).
Last-month rule:  If you are an eligible individual on the first day of the last month of your tax year (usually Dec. 1), you are considered an eligible individual for the entire year. 
Under the last-month rule, you must remain an eligible individual during the testing period.  The testing period begins with the last month of your tax year, and ends on the last day of the twelfth month following that month (e.g. Dec. 1, 2016 – December eligibility, 2017).
If you fail to maintain eligibility, the total contributions made to your HSA (except for the last-month rule) will be included as income in the year in which you fail to be eligible.  The amount is also subject to a 10% additional tax.
Contribution amounts must be reduced by any amount contributed to an Archer MSA in the same tax year.  This includes employer contributions to your Archer MSA.
Contributions cannot be made if you are on Medicare.

A High Deductible Health Plan (HDHP) is required in order to be eligible for a Health Savings Account.  HDHP requirements are shown below:

2016 HDHP Minimum Deductible:

For a single individual, an HSA-qualified health plan in 2016 must have a deductible no lower than $1,300.

For a family, an HSA-qualified health plan in 2016 must have a deductible no lower than $2,600.

2016 HDHP Maximum Out of Pocket:

For a single individual, the maximum out-of-pocket exposure on an HSA-qualified health plan cannot exceed $6,550.

For a family, the maximum out-of-pocket exposure on an HSA-qualified health plan cannot exceed $13,100.

2017 HDHP Minimum Deductible:

For a single individual, an HSA-qualified health plan in 2017 must have a deductible no lower than $1,300.

For a family, an HSA-qualified health plan in 2017 must have a deductible no lower than $2,600.

2017 HDHP Maximum Out of Pocket:

For a single individual, the maximum out-of-pocket exposure on an HSA-qualified health plan cannot exceed $6,550.

For a family, the maximum out-of-pocket exposure on an HSA-qualified health plan cannot exceed $13,100.