There is no single correct number
People often ask for a standard retention period, such as a number of days that every home or business should use. In general, there is no universal answer. How long to keep footage depends on what the cameras are for, how much storage you have, how quickly you would notice a problem, and what rules apply where you live or operate. The sections below describe the factors, so you can choose a period you can explain and defend.
Factor 1: How soon would you notice a problem?
Footage is only useful if it still exists when you realize you need it. A homeowner who checks cameras every day may need only a short period. Someone who is away for weeks, or a business that discovers a missing item during a monthly stock check, needs a longer one. Think about the longest realistic gap between an event and your finding out, then allow a margin. Notifications and alerts shorten that gap, but they are not infallible, so do not rely on them alone.
Factor 2: Storage capacity and recording mode
Retention is partly arithmetic. Storage size divided by daily use gives roughly the number of days a recorder can hold before overwriting. As a hypothetical example, suppose a camera produces 43.2 gigabytes a day when recording continuously, and the drive has 4 terabytes, or about 4,000 gigabytes set aside for it. Then 4,000 ÷ 43.2 is about 92.6, so roughly 92 days for that one camera. With four identical cameras sharing the drive, the figure drops to about 23 days. Motion-only recording usually stretches this considerably, though results vary with how busy the scene is. The point is that retention can be changed by adding storage, lowering the bitrate, or recording less often. The mechanics of video storage are covered in the overview of this topic.
Factor 3: Purpose of the cameras
A camera that watches a quiet side door for the unusual event may reasonably keep footage for a few weeks. A camera at a cash counter or shop floor may serve to resolve disputes or reviews of incidents that surface later. A camera that exists to check on a delivery or a visitor may need footage for only a day or two. Match the period to the realistic use, instead of defaulting to the maximum.
Factor 4: Privacy and data minimization
Footage of people is personal information in many places. Holding it longer than needed increases the risk that it is leaked, misused, or requested in a dispute. A reasonable principle is to keep what you have a legitimate reason to keep, and delete the rest on a regular schedule. Automatic overwriting helps because it applies the rule without anyone remembering. Data deletion practices, including how to delete recordings safely, deserve some attention, especially when cameras cover shared spaces or employees.
Factor 5: Local rules and obligations
Some places, and some kinds of business, have rules about how long recordings must or may be kept. These can come from privacy laws, workplace regulations, licensing conditions for particular industries, or insurance and contract terms. Others have no specific rules at all. This article cannot say what applies to you. Recording laws differ widely, so check with your local authority, trade body, or a qualified legal adviser, and ask your insurer or landlord if they have requirements. If the rules set both a minimum and a maximum, the period needs to fall between them.
Factor 6: Incidents and legal holds
Overwriting should have an exception. If something happens, such as a break-in, an injury, or a dispute, copy and set aside the relevant clips immediately instead of letting the recorder erase them on schedule. Export them with the date and time visible, keep a note of when and by whom they were saved, and store them securely. If police or an insurer ask for footage, sharing footage safely and lawfully takes some care. Once an incident is resolved, delete the saved copies when there is no longer a reason to keep them, unless a legal requirement says otherwise.
Common retention patterns
These are illustrations, not recommendations:
- Households often keep somewhere from a few days to a few weeks of motion-triggered clips, since problems tend to be noticed quickly.
- Small businesses sometimes keep a month or more, because disputes or discrepancies can come to light later.
- Sites with specific obligations may keep whatever their rules, contracts or insurers require, which could be longer or shorter than the above.
Choose a period based on your own reasoning and check the rules that apply, rather than copying a number from elsewhere.
Practical tips
- Write down the period you choose and why, especially for a business.
- Set the recorder to overwrite automatically, and confirm that it does.
- Check how much time is actually available by looking at the oldest clip on the recorder.
- Limit who can view, copy or delete footage, and use strong, unique passwords on accounts and devices.
- Revisit the period when you add cameras or change resolution, since both change storage use.
- Tell employees and visitors about cameras where required or appropriate, and be considerate of neighbors.
Remember that cameras and recordings cannot guarantee that an incident is captured or resolved. A thought-out retention period simply makes it more likely that useful footage still exists when you need it, without keeping more personal data than necessary.