According to the U.S Food and Drug Administration, the components of the ART kit can degrade over time, potentially affecting the diagnostic’s performance and accuracy. Hence, it is important for us to be mindful of their expiry dates.

However…

• The expiry dates are often set conservatively, and manufacturers are constantly revising them. So we may still be able to use test kits that have gone past their printed expiry date. 
• A US expert in the field has stated that “as long as ‘the control line is showing up and it’s within 18-24 months of the manufacture date, you should assume the test is working.” 

Is this another scam to get us to buy more tests when we don't need to??!

No! The short expiry dates were set in the early days of kit development. 

These rapid tests were developed very rapidly! In fact so rapidly there was no time to determine what a realistic shelf life was. Authorities, erring on the side of caution, set conservative expiry dates. 

In the US, many manufacturers are now revising these expiry dates and if you have a kit produced in the US, you can lookup online to see if your kit expiry has changed.

But that also means that if you bought a kit more recently, the expiry date may be more realistic than the early generations of kits. Be sensible!

More Info:

• TIME: At-Home COVID-19 Tests Expire. Here's What to Know About Yours
• Cnet: Your Expired COVID Test Kits Might Still Be Good. Here's How to Find Out - The shelf life of many COVID-19 test kits has been extended. See when yours really expire.
• ST: Australia left with millions of ART kits as expiry looms: “In some cases, the authorities in Australia have extended the original shelf life of the kits. Some test kits can now be used for up to 18 months after purchase compared with the original expiration periods of four to six months.”