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Post-Quantum Cryptography: What Businesses Should Do Before 2030
What post-quantum cryptography means for a normal business, the NIST dates to know and the inventory-first plan that avoids both panic and neglect.
Most of what protects your data online rests on a mathematical problem that today's computers can't solve in a useful time. A large quantum computer could solve it. Nobody knows when one will exist, and that uncertainty is exactly why the planning starts now.
What would actually break
Quantum computers threaten public-key cryptography: RSA, elliptic-curve cryptography and Diffie-Hellman. Those algorithms secure website connections (TLS), VPNs, digital certificates, code signing, signed documents and many messaging tools. Symmetric encryption such as AES-256 and standard hash functions are considered far less exposed, though key sizes may need to grow.
Harvest now, decrypt later
The risk isn't only about the day a quantum computer arrives. A patient attacker can record encrypted traffic or steal encrypted files today and store them until decryption becomes possible. If your data still matters in ten or fifteen years, such as health records, legal files, designs, government contracts or identity data, it deserves attention before that day.
The dates to know
| Date | What happened or is planned |
|---|
| August 2024 | NIST published the first post-quantum standards: [FIPS 203](https://csrc.nist.gov/pubs/fips/203/final) (ML-KEM) for key exchange, FIPS 204 (ML-DSA) and FIPS 205 (SLH-DSA) for signatures |
| After 2030 | NIST's transition plan (IR 8547) deprecates RSA-2048 and similar quantum-vulnerable algorithms |
| After 2035 | The same plan disallows them |
Reporting on the plan varies between draft and final wording, and the details at the margins have shifted, so check NIST's own publication before you cite exact parameters. A summary of the finalised report keeps both dates. Separately, research from Google in 2025 suggested that RSA-2048 might be broken with far fewer quantum resources than earlier estimates. It doesn't tell us the date, but it argues against waiting.
What a normal business should do
You aren't going to rewrite cryptography. The sensible work is housekeeping that pays off whatever the quantum timeline turns out to be.
- Make an inventory. List where you use encryption: your website and API certificates, VPN, email signing, document signing, device encryption, backups and any custom software.
- Rank by shelf life. Data that must stay secret for ten years or more comes first.
- Ask your suppliers. Cloud, VPN, identity and software vendors should have a post-quantum plan. Ask for it in writing and note who has none.
- Aim for crypto-agility. Avoid hard-coding algorithms in your own software. You want to swap them without rebuilding everything.
- Plan upgrades with the normal lifecycle. Replace ageing equipment and certificates with products that support the new standards, instead of a special project.
- Watch the standards. Browsers and major cloud providers are already adding hybrid key exchange, which combines classical and post-quantum methods.
Don't buy a miracle. Be wary of anything sold as "quantum-proof" without naming the standard it follows. Ask which NIST algorithm it uses and who has tested it.
What not to do
- Don't panic and rip out working systems. A rushed migration creates its own security holes.
- Don't ignore it either. Large organisations and governments have deadlines, so their suppliers will have deadlines too.
- Don't confuse this with quantum key distribution, a separate, hardware-heavy technology that most businesses won't need.
Where this fits in your wider plan
Post-quantum work is one item on a long list. For most small firms, multi-factor sign-in, patching and tested backups reduce far more risk today. See our small business cybersecurity checklist and the 2027 trends guide for the order to tackle things in.
A simple crypto inventory
You can build this in a spreadsheet in an afternoon. The goal is to see where public-key cryptography sits and which items are hard to change.
| Area | What to record | Question to ask |
|---|
| Websites and APIs | Certificates, where they're issued and when they expire | Can the host or provider support post-quantum key exchange yet? |
| VPN and remote access | Product, version and algorithms in use | What is the vendor's roadmap and timeline? |
| Email and document signing | Tools and certificate sources | How long must signatures stay valid? |
| Devices and backups | Encryption method and key storage | Is the data long-lived, and who holds the keys? |
| Custom software | Libraries and any hard-coded algorithms | Can we change the algorithm without rewriting the system? |
| Suppliers | Which of them encrypt your data, and how | Have they published a migration plan? |
Questions to put to vendors
- Which NIST post-quantum algorithms do you plan to support, and by when?
- Do you support hybrid key exchange today?
- How will you notify us of required upgrades or certificate changes?
- Is any of our data encrypted with keys you control, and how long are they valid?
- What will it cost us, if anything, to move?
A sensible three-year path
- 2027: finish the inventory, rank by data lifetime and send the vendor questions.
- 2028: turn on hybrid key exchange where your providers support it, and plan certificate and device replacements around normal lifecycles.
- 2029 and 2030: replace the items on the list that cannot be upgraded, and retire old algorithms in line with your suppliers' timetables.
This path is our suggestion, not a mandate. Your regulators, clients or suppliers may impose different dates.
Myths worth dropping
- "Quantum computers will break everything overnight." The change is gradual, and the planning window is years long.
- "Our business is too small to matter." Attackers collect data in bulk, and your suppliers' timelines affect you anyway.
- "We can wait until a standard is forced on us." Inventories and vendor questions take time, and long-lived data is exposed today.
- "Post-quantum means buying special hardware." For most businesses it means software updates and new certificates from your providers.
Get your inventory started
The hardest part is knowing what you have. Webbit's team can map where encryption and certificates are used across your websites, cloud accounts and connected tools, then rank them by how long the data has to stay secret. Book a free consultation and we'll suggest where to start, or read about our cybersecurity services.
Frequently asked questions
What is post-quantum cryptography?
Encryption and signature methods designed to resist attacks from both classical and quantum computers. NIST published its first standards in August 2024.
When will quantum computers break encryption?
Nobody knows. Estimates vary widely, and research keeps changing them. NIST's plan uses 2030 and 2035 as planning dates for retiring today's public-key algorithms.
Does this affect small businesses?
Indirectly, and soon. Your cloud, VPN and software suppliers will migrate, and your job is to ask about their plans and avoid hard-coding old algorithms. Businesses with long-lived sensitive data have more to think about.
Is AES encryption safe against quantum computers?
AES-256 is widely considered safe against known quantum attacks. The main exposure is public-key cryptography such as RSA and elliptic curves.
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