If your target market is other IT firms, then calling yourself an MSP is the right move. IT professionals know what this means. But — and this is really important — most other people don’t know what an MSP is.
Whatever you call your type of business, your prospects should instantly know what you do. If you have to explain what “managed service provider” or “MSP” means, then there is a good chance that people who could be potential clients may never understand what you do and therefore will move on instead of contacting you.
This means that for prospects to find you online, your marketing — that’s your website, your blog, your digital content — has to use terms that your clientele thinks of when they look for IT services. And that doesn’t always mean MSP.