Why does my internet drop at the same time every day?

A regular, predictable drop is a strong clue, because genuinely random faults do not keep a schedule. There are a handful of mechanisms that produce this pattern.

Some providers enforce a periodic reconnection, historically every twenty-four hours, which briefly interrupts the connection and often changes your public address. It is a policy rather than a fault, though many providers let you influence the timing.

Address lease renewal produces a similar effect. Devices and routers hold their addresses for a fixed period and renew them periodically. Renewal is normally seamless, but a misconfiguration or a conflict makes it visible as a brief outage at regular intervals.

Scheduled activity on your own network is the next candidate. Backup software, system updates, security scans and synchronisation tools often run at fixed times and can saturate the connection or, on some routers, exhaust connection tracking capacity. The connection is not dropping so much as becoming unusable, which is hard to distinguish without looking.

External interference can also be scheduled without being obvious. Equipment on a timer, outdoor lighting, and in some cases a neighbour returning home and their devices reconnecting, all recur daily.

Finally, congestion at peak hours is not a drop but degrades enough to look like one, and follows an obvious daily pattern in the early evening.

Distinguishing between them is mostly a matter of logging. Most routers record connection events, and the log will show whether the link genuinely went down, whether an address was renewed, or whether nothing happened at the router at all, which points at your own device or at congestion instead.