Diagnostic tests can show if you have an active COVID-19 infection and need to take steps to quarantine or isolate yourself from others.

This page is part of the FAQs on Testing for SARS-CoV-2 and provides answers to frequently asked questions related to at-home COVID-19 diagnostic tests.

Q: Can I use an authorized at-home COVID-19 diagnostic test if it was left outside in freezing temperatures? (1/22/22)

A: Since shipping conditions may vary, test developers perform stability testing to ensure that the test performance will remain stable when tests are stored at various temperatures, including shipping during the summer in very hot regions and in the winter in very cold regions.

However, test performance may be impacted if the test is used while it is still cold, such as being used outdoors in freezing temperatures or being used immediately after being brought inside from freezing temperatures. The stated performance generally assumes the test is being performed in an environment that is between 15-30⁰C (approximately 59-86⁰F). The specific conditions that were validated are included in the authorized Instructions for Use for each test.

In order to ensure appropriate test performance with a test that is delivered to you in below freezing temperatures, you should bring the package inside your home and leave it unopened at room temperature for at least two hours before opening it. Once the package is at room temperature, you may open it and perform the test according to the authorized instructions for use. As long as the test line(s) appear as described in the instructions, you can be confident that the test is performing as it should. If the line(s) do not appear in the correct location(s) and within the correct time as shown in the test instructions when you perform the test, then the results may not be accurate, and a new test is needed to get an accurate result.

If you think you had a problem with a COVID-19 test, the FDA encourages you to report the problem through the MedWatch Voluntary Reporting Form.

If you have questions, email the Division of Industry and Consumer Education (DICE) at [email protected] or call 800-638-2041 or 301-796-7100.