Ask a Fool: How Does a Spousal IRA Work?
It's true that one of the eligibility requirements to contribute to an IRA is earned income. The 2019 IRA contribution limit is $6,000 ($7,000 if you're 50 or older) or your total earned income for the year, whichever is less.
However, there's an exception for married couples if only one spouse works. If this is the case, the working spouse can contribute to an IRA on behalf of both partners, up to both spouses' annual contribution limits. This is known as a spousal IRA.
There are a few requirements to keep in mind. First, the working spouse must have enough earned income to justify both contributions. Second, both spouses must meet the IRS income limitations for the type of IRA you're contributing to -- even though your spouse doesn't work, your income could potentially disqualify them in some cases. And finally, in order to qualify for a spousal IRA, the couple must file a joint tax return.
Source Fool.com