Manual method
- For the French personal-tax example, sign into impots.gouv.fr and open Documents.
- Choose a year, open the relevant document’s PDF version and save it; repeat for each year/type required.
- Separately preserve submitted return files, confirmation receipts and accounting-software exports you control.
- Record which documents are filed versions versus drafts, and verify that important signed PDFs still open.
Coverage and limitations: Country, tax authority and accounting products determine the actual export routes. The French example is not worldwide guidance. Do not treat preservation advice as a decision about how long legal records must be retained.
Size and time to allow
Illustrative planning size: 0.5 GB; scenario range 0.01–10 GB. This is a storage-planning example, not a measured average. Your archive may be smaller or larger. Ten years of returns/notices, working spreadsheets and supporting PDFs; a business archive can be far larger.
Preparation and hands-on time: Existing PDFs are available as downloads; budget 20–60 minutes for several years. Missing records depend on the authority.
For the 0.5 GB example, network transfer alone is approximately:
| Connection download speed | Transfer estimate |
|---|---|
| 10 Mbit/s | 10 min |
| 50 Mbit/s | 2 min |
| 100 Mbit/s | 58 sec |
These calculations use decimal GB and 70% of the advertised speed. Tiny transfers can take longer because of startup overhead. Local exports do not need an internet download; use these numbers only for a network transfer. Preparation, retries, extraction, checking and a cloud upload are additional; use upload speed for the latter.
Where and how to keep it
An encrypted USB key can hold this example, but keep another independent copy on an external drive or in private encrypted cloud storage. A USB key alone is easily lost and is not a complete preservation plan. These files expose sensitive identity or financial details; avoid shared folders and retain an independent recovery method.
Create a dated tax_records/YYYY-MM-DD/ folder. Keep received originals unchanged, use a separate working copy, and note the account/profile, selected dates, formats and known gaps in a private README. Compare file sizes, check any supplied checksums, and open sample files from the backup before considering the task finished. Repeat after meaningful additions. Follow the storage, archive-checking and large-file guide.
Sources and review
Public documentation was reviewed on 27 October 2026. No signed-in export or restoration was performed. Account options and availability can change; follow the current provider instructions.