Is there a deadline for setting up and contributing to an HSA?

Is there a deadline for setting up and contributing to an HSA?: There is no deadline to set up an HSA. HSAs can be created and contributed to at any time*. However, HSA set up and contributions must be completed before the tax return due date to apply to the current tax year. Any contributions made after April 15 are applied to the following tax year. Extensions with the IRS do not affect this date.; *Subject to the terms of the HSA custodial agreement.