Data Transfers · Progress, pausing and history
How many transfers run at the same time?
Short answer: Two transfers run at once; the rest wait as Queued and start automatically when a slot frees up. Within each transfer, several files move at once according to the Parallel transfers setting.
Two transfers run at once; any others wait with the Queued state and start automatically as soon as a slot frees up, in the order they were added. This keeps your Mac and your connection responsive.
Inside each transfer, several files can move at the same time — that's set by Parallel transfers under Advanced options.
If a transfer stays Queued for a long time, check whether two others are running or paused-and-waiting, and whether it needs a drive that isn't connected.
Related: Parallel transfers setting · Transfer states explained