What Questions Should Developers Ask Before Buying a Code Signing Certificate?

Developers need to verify certificate type compatibility, validation requirements, key storage security, platform support, and total costs before purchasing a code signing certificate. The wrong choice can delay releases, create security vulnerabilities, or waste budget on features you don’t need.

Code signing certificates authenticate your software and confirm it hasn’t been tampered with since you signed it. Microsoft, Apple, and other platforms require signed code to avoid security warnings that scare users away.

Asking the right questions before purchase prevents common mistakes:

Code Signing Certificate Buying Guide

Who This Guide Is For

This guide is written for:

What Type of Code Signing Certificate Do I Need?

You need either an Organization Validation (OV) or Extended Validation (EV) code signing certificate depending on whether you require immediate SmartScreen reputation on Windows.

EV certificates require stricter validation but provide immediate SmartScreen reputation, eliminating download warnings from day one. The tradeoff is higher cost and mandatory hardware token storage. Understanding the differences between OV and EV code signing certificates helps you make the right choice for your distribution needs.

Which Operating Systems and Platforms Must Be Supported?

Your certificate must explicitly support every platform where you distribute software – Windows, macOS, Linux, mobile platforms, and specialized systems like kernel drivers.

Driver signing for Windows kernel-mode code requires EV certificates exclusively. According to Microsoft’s driver signing documentation, all kernel-mode drivers submitted after July 2021 must be EV signed.

If you’re developing Java applications, you’ll need to understand how Java code signing certificates work since they use different keystore formats than Windows executables.

Action steps before purchase:

Do I Need an EV (Extended Validation) Certificate for Trust & SmartScreen?

You need an EV certificate if you distribute Windows software to users outside your organization and want to avoid SmartScreen warnings immediately.

Windows SmartScreen builds reputation based on download frequency and user feedback. Analysis from SSLInsights Code Signing Certificate Windows Applications guide indicates newly signed applications typically need 500-2,000 downloads before SmartScreen stops warning users.

OV vs EV Decision Factors:

EV certificates cost 2-3x more than OV certificates and require hardware security modules or USB tokens for private key storage. You can’t automate EV signing in cloud CI/CD pipelines the same way as OV certificates.

How Will the Private Key Be Stored and Secured?

Your private key storage method determines both security and workflow compatibility – hardware tokens provide maximum security but complicate automation, while cloud HSMs enable CI/CD integration with proper access controls.

Private Key Storage Options:

EV certificates mandate hardware storage on FIPS 140-2 Level 2 certified USB tokens or HSMs. OV certificates offer more flexibility through cloud HSM services or password-protected PFX files.

A 2024 NCSC report on software supply chain security identified exposed code signing keys as a primary attack vector for malware distribution.

Which Certificate Authority (CA) Should I Trust?

Choose a CA that’s trusted by your target platforms, offers reliable support, and maintains clean security practices.

Verify your CA appears in these trust programs:

Mozilla’s CA incident dashboard tracks CA incidents and trust status as of 2025. When evaluating providers, consider reading comparisons of leading code signing certificate providers to see which offers the best combination of trust, support, and pricing.

How Long Is the Certificate Valid?

Code signing certificates are currently valid for one or three years, with industry standards moving toward shorter validity periods.

One-year certificates cost less upfront and let you switch CAs annually. Three-year certificates offer 15-20% total discounts and reduce renewal overhead but lock you into a single CA.

Certificate expiration doesn’t invalidate previously signed software. Applications signed with an expired certificate continue working as long as the signature included a timestamp from when the certificate was valid.

What Validation Documents Are Required?

CAs require business registration documents, identity verification, and additional authentication depending on validation level.

OV Certificate Validation Requirements:

EV Certificate Additional Requirements:

Typical Validation Timelines:

Gather documents before purchasing. Incomplete documentation extends validation timelines and can delay product releases. If you’re preparing to apply, review the detailed guide on how to get a code signing certificate to understand the complete process.

Will This Certificate Work With My Build & CI/CD Pipeline?

Certificate compatibility with your build tools depends on key format support, API availability, and whether you’re using hardware tokens or cloud HSMs.

Cloud CI/CD Integration:

Hardware EV tokens complicate automation since you can’t plug a USB token into cloud build agents.

Solutions for EV certificate automation:

Test your complete signing workflow during CA evaluation. Some CAs offer trial certificates for integration testing.

Does the Certificate Support Timestamping?

Your certificate must support RFC 3161 timestamping to keep signed software trusted after certificate expiration – this is non-negotiable for production software.

Timestamping adds cryptographic proof that code was signed while the certificate was valid. Without timestamps, signatures become invalid when certificates expire.

Impact of Missing Timestamps:

According to NIST’s guidance on software supply chain security (SP 800-204D), timestamp validation is a required step in software supply chain verification. Learn more about what time stamping is and why it’s essential for long-term code trust.

Verify during purchase:

What Happens If My Certificate Is Compromised or Revoked?

Certificate compromise requires immediate revocation, which invalidates all previously signed software and forces emergency re-signing with a new certificate.

Recovery steps:

Timestamped signatures survive revocation only if the timestamp proves signing occurred before compromise.

Are There Hidden Costs?

Certificate sticker prices exclude renewal markup, replacement fees, reissuance charges, and required hardware costs.

Total Cost of Ownership:

Request total cost estimates including:

A $200 certificate with unlimited free reissuance beats a $150 certificate that charges $75 per reissuance if you anticipate organizational changes.

Will My Signed Software Be Trusted Globally?

Global trust depends on your CA’s presence in platform trust stores worldwide and compliance with regional signing requirements that vary by country.

Windows in China uses the China Internet Network Information Center (CNNIC) root program alongside Microsoft’s global program.

Export regulations affect code signing:

How Easy Is Renewal and Re-Verification?

Certificate renewal requires repeating validation steps, though established customers often receive streamlined processing.

Renewal reminder schedule:

Is Support Available When Something Breaks?

Certificate authorities vary wildly in support quality – expect 24/7 phone support from premium CAs and email-only support during business hours from budget providers.

Common support scenarios:

Budget providers offering rock-bottom prices typically provide minimal support. Premium CAs charge more but include responsive technical assistance worth the difference when releases depend on working signatures.

Choosing the Right Code Signing Certificate

The right code signing certificate balances security requirements, platform compatibility, workflow integration, and total cost of ownership.

Start with these foundation steps:

Final checklist before purchase:

Priya Mervana

Verified Web Security Experts

Priya Mervana is working at SSLInsights.com as a web security expert with over 10 years of experience writing about encryption, SSL certificates, and online privacy. She aims to make complex security topics easily understandable for everyday internet users.