Don't worry! Episode Alert has you covered
It may seem like a scary new change. But luckily CMS has decided to make this a long transition. In fact, CMS will begin mailing patients new MBI numbers starting on 4/1/18 and ending on 12/31/19.
The great thing is CMS knows this may take everyone some time to get used to these new Medicare Beneficiary Identifiers so don't worry if you run into a patient who has not received theirs in the mail. You will still be allowed to use their Health Insurance Claim Number (HICN) all the way until January 1st, 2020. After that date, Medicare will only accept the Medicare Beneficiary Identifier (MBI).
You may be asking yourself Why all the changes? Well, the biggest reason is simple. Medicare wants to protect patients from medical identity theft.
Here is a link to CMS overview. There you can find out all the Information you may need.