There is no one answer to this question that covers every company and every record label, but the simple response could be yes.
Record labels are always looking for new talent, for the next great artist, and one of the ways they find these people and bands is via demos. Keep this in mind as you push to be heard by someone at a label–they need you (or someone like you) as much as you need them.
Basically, record labels will let you know if they accept demos or not. Most of the larger, well-known brands will say they don’t, but as the rest of this article explains, there are ways around that answer…even if they’re a bit sneaky.
Those companies that explicitly say they are open to demos do try to get around to listening to what comes in, though you need to be patient. Because they’re open to welcoming new artists, they are likely inundated with submissions, so it may take them quite a long time to get to yours.
It’s also worth mentioning that in today’s all-online world, demos don’t mean what they used to. A CD with your recordings is no longer the only way for a record label to hear you. Your “demo” might actually be an email with links to your Spotify profile, so perhaps that word isn’t a great fit anymore. Instead, think in terms of submissions, as opposed to a proper demo. If this is the case, you might want to do everything you can to ensure your music sounds less like a demo (meaning unfinished) and more like a ready-to-go smash.