Is PDF/A better than PDF for archiving business records?

Yes. PDF/A is an ISO-standardised format built for long-term preservation. It embeds fonts, colour profiles, and metadata inside the file and removes external dependencies and active content, so the document looks the same decades later. Standard PDF is more flexible for working files but is not guaranteed to reproduce identically over long retention periods.

Do I still need TIFF if I have PDF/A?

For most general business records, no. PDF/A covers long-term archiving with the added benefit of a searchable text layer. TIFF is still useful for high-fidelity imaging such as engineering drawings, historic deeds, and certain e-disclosure workflows that mandate single-page TIFF, but it produces larger, non-searchable files for everyday documents.

How long must UK businesses keep records?

It varies by record type. Company accounting records must be kept for at least six years under the Companies Act 2006, PAYE records for at least three years after the tax year, and some health and safety exposure records for up to 40 years. Long retention periods are a key reason to archive in a stable format such as PDF/A.

Are scanned PDF/A files acceptable as legal evidence in the UK?

Scanned documents can be accepted as evidence provided you can demonstrate they are accurate, complete, and captured under a reliable, auditable process. PDF/A supports this because it is a stable, self-contained format with embedded metadata, but sound scanning procedures, indexing, and chain of custody matter just as much as the file format itself.

Can documents be converted to PDF/A after they have been scanned?

Yes, existing PDFs and images can be converted to PDF/A, but results are best when the original capture was high quality. Converting a low-resolution or poorly OCR'd archive rarely produces a perfect result, so it is more reliable to capture correctly and output PDF/A as part of the original scanning workflow.

PDF vs PDF/A vs TIFF: Which File Format Is Best for Business Records?

For most UK businesses, PDF/A is the best format for records you need to keep and trust for years, plain PDF is best for everyday working documents, and TIFF still has a place for high-fidelity image capture. The right choice depends on how long you must retain the file, whether it needs to be searchable, and whether it may one day be used as legal or audit evidence. Getting this decision right at the point of scanning saves expensive re-work later, because converting a badly captured archive after the fact is slow, costly, and rarely perfect.

What each format actually is

All three are widely used in document scanning projects, but they solve different problems.

PDF — the everyday document format. It can hold text, images, and a searchable text layer produced by OCR. It is flexible and universal, but a standard PDF can embed fonts, links, JavaScript, and external references that may not display identically in ten years’ time.
PDF/A — a restricted, ISO-standardised version of PDF (ISO 19005) designed specifically for long-term archiving. Everything needed to reproduce the document is embedded in the file itself: fonts, colour profiles, and metadata. No external dependencies, no active content. It is the format built to survive.
TIFF — a high-quality raster image format that has been an industry standard for decades. It captures a faithful picture of the page but, on its own, holds no searchable text. Multi-page TIFFs are common in legacy scanning and litigation workflows.

Why PDF/A wins for records you must retain

UK retention periods are long. Statutory employee records under PAYE must be kept for at least three years after the end of the tax year, health and safety records for employees exposed to hazardous substances can run to 40 years, and pension and construction records frequently outlive the people who created them. Company accounting records must be kept for six years under the Companies Act 2006, and longer for public companies.

A document you open in 2046 needs to look exactly as it did when you scanned it. PDF/A is engineered for precisely that. Because fonts and colour data are embedded, the file does not rely on software or fonts that may have vanished. That self-contained quality is why national archives, courts, and regulated sectors specify PDF/A for permanent records. If a file might ever be produced in a GDPR subject access request, an employment tribunal, or an HMRC enquiry, PDF/A gives you the strongest footing.

PDF/A flavours worth knowing

PDF/A-1b — guarantees faithful visual reproduction. The safe baseline.
PDF/A-1a / PDF/A-2a — add tagged structure and full text accessibility, useful where accessibility obligations apply.
PDF/A-2 and PDF/A-3 — support better compression (JPEG2000) and, in the case of A-3, embedding source files such as the original spreadsheet alongside the archived page.

When plain PDF is the right call

Not every document needs archival-grade treatment. For active files that circulate, get edited, are signed digitally, or are superseded within a year or two, standard PDF is the pragmatic choice. It supports interactive forms, digital signatures, hyperlinks, and comment layers that PDF/A deliberately strips out. A supplier quote, a draft contract, or a working project pack is better as a normal PDF.

The sensible pattern for many UK businesses is a two-tier approach: work in PDF, then convert to PDF/A at the moment a document becomes a fixed record — when a contract is executed, an invoice is settled, or a case is closed. A good scanning partner can automate that conversion as part of the capture workflow rather than leaving it to individual staff.

Where TIFF still earns its place

TIFF has lost ground to PDF/A, but it is not obsolete. It remains valuable where an exact, uncompressed pixel-for-pixel image matters — engineering drawings, historic deeds, medical imaging, and some litigation e-disclosure processes that still specify single-page TIFF plus a separate load file. Because TIFF supports lossless compression, it avoids the JPEG-style artefacts that can blur small print or signatures.

The trade-offs are real, though. TIFF files are large, they are not searchable without a separate OCR text file, and they lack the embedded metadata and standardised archival guarantees of PDF/A. For most general business records — HR files, finance paperwork, correspondence — TIFF creates more storage and indexing overhead than it repays.

A quick decision guide

Long-retention records, compliance, potential legal evidence → PDF/A (A-1b or A-2b as standard).
Active, editable, or short-life working documents → standard PDF with a searchable OCR layer.
High-fidelity imaging, drawings, or format-mandated e-disclosure → TIFF, ideally paired with an OCR sidecar for search.
Mixed archives → capture once at high quality, output PDF/A for the record copy, and keep working copies as needed.

Whichever format you choose, capture quality is what determines whether the result is genuinely usable: 300 dpi as a minimum for text, accurate OCR, and consistent file naming and indexing so documents can actually be found again. Format is only half the job — a perfectly compliant PDF/A that nobody can locate is no better than a lost box. If you are weighing up how to combine digital access with your existing archive, our guide on document storage and retrieval and the wider resources library cover the practical steps.

The bottom line

Default to PDF/A for anything you have to keep, prove, or defend; use plain PDF for live working files; and reserve TIFF for the narrow cases where exact image fidelity or a mandated format demands it. A professional scanning provider can apply these rules automatically at the point of capture, so your team gets searchable, compliant, future-proof files without having to think about ISO standards on every document.