Anyone with earned income can open and contribute to an IRA, including those who have a 401 (k) account through an employer. The only limitation is on the total contributions to your retirement accounts in a single year. It depends on what type of IRA it is. Just about anyone can contribute to a traditional IRA, as long as you (or your spouse) receive taxable income and are under 70 and a half years old.
However, your contributions are tax-deductible only if you meet certain requirements. For more information on those qualifications, see Who can contribute to a traditional IRA?.