How to Share Your Mac Screen (Built-In Screen Sharing)

macOS has had full remote-control screen sharing built in for nearly two decades — no Zoom, no TeamViewer. One switch lets another Mac view or drive yours over the local network, and Messages extends it across the internet, which makes it the easiest way to fix a parent's Mac from another city. Here's the setup and the three ways to connect.

Turn it on (the Mac being shared)

1. Open System Settings → General → Sharing.
2. Turn on Screen Sharing.
3. Click the ⓘ next to it to control who may connect: All users, or Only these users with an explicit list. Keep it restrictive — anyone allowed here can see and control everything.

One conflict to know about: if Remote Management is enabled (used by schools and workplaces), Screen Sharing can't be switched on separately — Remote Management already includes it.

Connect from another Mac on the same network

Three routes, same result:

• Finder sidebar: the shared Mac appears under Network (or in Go → Network). Select it and click Share Screen… in the window header.
• The Screen Sharing app: press Cmd+Space, type "Screen Sharing", and enter the other Mac's name, IP address, or Apple ID. On macOS 15 Sequoia this app got a real redesign — a connection list that remembers every Mac you manage.
• Connect to Server: in Finder, Cmd+K, then vnc://the-macs-name.local — the old-school route, useful in scripts and bookmarks.

Sign in with a user account from the remote Mac (or an allowed Apple ID). Once connected you get the full desktop in a window: your keyboard and mouse drive it, the shared clipboard carries copy-paste both directions, and the toolbar toggles between controlling and merely observing.

Across the internet: use Messages

For anything beyond your own network, skip port forwarding — Messages does the tunneling for you, as long as both Macs are signed into iMessage:

1. Open the conversation with the other person in Messages.
2. Click the ⓘ info button at the top right of the conversation.
3. Click Share, then choose Invite to Share My Screen — or Ask to Share Screen to see theirs.

The other side gets a prompt to accept. Viewing starts immediately; to drive their Mac, they additionally grant control from the screen-sharing notification — a sensible second gate. Audio opens alongside so you can talk while you fix. This is the single best tool for remote family tech support that almost nobody knows exists.

Lock it back down

When the session's done, the undo is the same switch: System Settings → General → Sharing → Screen Sharing off. If you only ever share via Messages, leave the Sharing switch off entirely — Messages sessions are per-invitation and don't need the standing service. And if a session ever behaves oddly, both sides can kill it instantly from the menu bar's screen-sharing icon.