Some Galaxy S21, S21 + and S21 Ultra units do not support MST for Samsung Pay. The availability of the feature seems to vary by country – some understand it, others do not, and not in a way that makes sense.
MST allows the phone to work with terminals that only support old school magnetic stripe cards. This is a big issue in the US where such terminals are fairly common, less so in regions where NFC terminals are plentiful.
Unfortunately, the S21 phones sold in the US are in the group that does not have MST. Phones sold in the UK do have it. Is it due to the different slides (Snapdragon in the US, Exynos in Europe)?
That does not appear to be the case. The specifications of the French, Italian and German press releases make no mention of MST. The Dutch mention MST, as well as the Polish, Russian and Indian press releases.
Here’s a statement from Samsung on the matter at the request of XDA:
Due to the rapid adoption of NFC technology (NFC) by consumers and businesses, starting with devices launched in 2021, Samsung Pay will focus its support on NFC transactions in the Galaxy portfolio. While future devices will no longer include magnetic stripe technology (MST), customers with previous compatible Galaxy devices may continue to use Samsung Pay, including MST.
MST was launched in 2015 with the Galaxy S6 and has been a major part of the best Galaxy ever since. Now it has one foot out the door.
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