There are two main ways to organize archived email. The first, older one uses folders: each message sits in one place only, like a sheet in a filing cabinet. The second, made popular by Gmail, uses labels: each message can have zero, one or more labels, and stays in a single archive. Understanding the difference helps you choose a suitable scheme and avoid surprises when you use the same account from different programs.
Folders: one place for each message
With folders, moving a message means taking it out of one place and putting it in another. It is an intuitive model and works well when each message clearly belongs to a single category: a supplier's invoices, correspondence with a client, notices from the building manager.
The limit appears with messages that concern several things at once. An email from your accountant about both your tax return and a lease contract: does it go in «Taxes» or «Home»? Whatever you choose, one day you will look for it in the other.
Labels: several categories for the same message
With labels the same message can be «Taxes» and «Home» at the same time, without duplicating it. Archiving simply means removing the «Inbox» label: the message stays in «All mail» and appears under every label assigned to it.
It is a more flexible model, but it takes some discipline: without rules, labels multiply until they become as useless as a «Misc» folder.
What happens with IMAP
Many people use the same account both on the web and with a client such as Outlook, Thunderbird or Apple Mail, connected via IMAP. The IMAP protocol only knows folders. That is why Gmail, when read over IMAP, presents each label as a folder. This leads to some behaviours worth knowing:
- a message with two labels appears in two folders in the client, even though it exists only once on the server;
- moving a message from one label-folder to another in the client amounts to changing its label;
- deleting a message from a label-folder in the client may simply remove the label rather than truly delete it; the behaviour depends on the account's IMAP settings.
It is worth checking these settings before doing a big clean-up from a desktop client.
Which scheme to choose
Whatever the tool, the archiving scheme should be simple. An approach that works for most people:
- A general archive where almost everything goes, searchable.
- A few categories for what you consult as a whole: active projects, administrative documents, receipts.
- A temporary category for things that are waiting on something: a reply, a delivery, a refund. Empty it often.
An example scheme, valid with either folders or labels:
Archive
Projects/Client-Bianchi
Projects/Association-website
Admin/Bank
Admin/Home
Receipts
Waiting
Many clients let you nest categories, as shown with the slash. Do not go beyond two levels.
Search as the main tool
With archives of tens of thousands of messages, the tool you use most is not folders but search. Learning a few search operators changes the experience. Here are some examples in Gmail, similar to those available in other services:
| Operator | What it finds |
|---|---|
from:supplier.com |
messages from that domain |
has:attachment filename:pdf |
messages with PDF attachments |
after:2025/01/01 before:2025/04/01 |
messages in a date range |
subject:invoice |
a word in the subject |
larger:10M |
messages larger than 10 MB |
Outlook offers similar operators, such as from:, hasattachments:yes and received:, and almost every client has an advanced search with separate fields.
Saved searches
If you often repeat the same search, for example «invoices with attachments from this year», many clients let you save it as a virtual folder or search folder. The result updates itself and you do not have to move anything. It is often a better alternative to creating a real folder.
Space and cleanup
Mail archives grow mainly because of attachments. Once a year, a search for messages larger than a few megabytes brings up presentations, videos and scans that you can save in your computer's folder structure and then delete from your mail. Keep the original message, though, when it contains important information such as a confirmation or an agreement.
In short
- Folders put each message in one place; labels allow several categories.
- Over IMAP labels become folders: check what deleting from the client means.
- Use a general archive and a few categories, at most two levels deep.
- Learn a few search operators and use saved searches.
- Once a year, look for the heaviest messages and move useful attachments.
