What are my HSA contribution limits if one, but not all members of the family are covered by an HSA-eligible plan?

Question

My understanding is that when a person enrolls in an HSA-compatible health plan, he may contribute $3300 to an HSA.

For example, if Adam is enrolled in an HSA-compatible plan, he may contribute $3300 to his HSA.

If a family is covered by an HSA-compatible health plan, they may contribute $6550 to an HSA.

For example, if Bob is married and his family is covered by an HSA-compatible health plan, he may contribute $6550 to an HSA.

Both examples above are so simple as to be obvious.

Now, suppose we look at Charlie, who is also married. Charlie's situation is different because Charlie is covered by an HSA-compatible plan, but Charlie's wife is covered by a completely different plan that is not HSA-compatible.

Is Charlie's contribution limit $3300 or $6550? If Charlie errantly contributed more than he is allowed, (say he contributed $6550, but was only eligible to contribute $3300), what are the consequences of this?

Answer 1

Charlie would have to have a family or employee-plus-one HSA-compatible plan to contribute the family limit ($6550 for 2014). Importantly, those covered under his plan cannot have non-HSA-compatible coverage. From the IRS:

Other health coverage. You (and your spouse, if you have family coverage) generally cannot have any other health coverage that is not an HDHP. However, you can still be an eligible individual even if your spouse has non-HDHP coverage provided you are not covered by that plan.

Lower down on the same page it talks about how to deal with excess contributions. You definitely want to withdraw the excess or else you get hit with a 6% tax on it every year. The withdrawal, along with earnings on the excess contributions, needs to be done before you file your taxes.

Answer 2

assuming charlie is not covered by his wife's plan (or any other non-hdhp), then he can contribute to an hsa. how much he can contribute depends on the hdhp plan type under which he is covered. if charlie signs up for a family hdhp (or an employee plus x hdhp), then he can contribute up to the family limit regardless of whether other plan members (e.g. his wife, child) are covered by other health insurance.

from the irs:

For 2015, if you have self-only HDHP coverage, you can contribute up to $3,350. If you have family HDHP coverage, you can contribute up to $6,650.

and

Self-only HDHP coverage is an HDHP covering only an eligible individual. Family HDHP coverage is an HDHP covering an eligible individual and at least one other individual (whether or not that individual is an eligible individual).

and

To be an eligible individual and qualify for an HSA, you must meet the following requirements.

You must be covered under a high deductible health plan (HDHP), described later, on the first day of the month.

You have no other health coverage except what is permitted under Other health coverage , later.

You are not enrolled in Medicare.

You cannot be claimed as a dependent on someone else's 2015 tax return.

and, just to be super-clear on the OP's specific situation:

If you meet these requirements, you are an eligible individual even if your spouse has non-HDHP family coverage, provided your spouse's coverage does not cover you.

side note: this assumes you are covered by an hdhp for the entire year. if you are only covered by an hdhp for part of the year, then your contribution limit may be pro-rated (with exceptions, of course).