Secure Hundreds of Domains and Subdomains With a Single Certificate
Multi-Domain SSL Certificates
Multi-domain SSL certificates allow a single certificate to secure multiple domains, including subdomains of a single main domain name or entirely different domain names. This type of digital certificate is also commonly referred to as a UCC SSL (Unified Communications Certificate) or a SAN SSL (Subject Alternative Names). They work well for businesses with multiple websites and/or servers to secure. They’re often used for Microsoft Exchange servers and Office communications servers and will operate as multi-domain SSL certificates if the number of servers is more than three. Sectigo® offers Domain Validation, Organization Validation, and Extended Validation options.
To obtain this type of SSL/TLS certificate, an organization must confirm details including legal company name, location, and domain name ownership. There is then a vetting process that must be completed by a human before the certificate is issued. Sectigo, a leading Certificate Authority (CA), offers both single-domain and multi-domain (UCC / SAN) Extended Validation Certificates.

Multi-Domain DV
Ideal for blogs & sites that don’t gather customer data
Fastest Issuance
12/5 Expert Service
Unlimited Server Licenses
2048-bit encryption
30-Day Money Back Guarantee
Compatible with all leading web and mobile browsers
Server Linux
Includes Nisse-SSL Trust Seal

Multi-Domain OV
Ideal for business sites and login screens
Validates Organization
12/5 Expert Service
Unlimited Server Licenses
2048-bit encryption
30-Day Money Back Guarantee
Compatible with all leading web and mobile browsers
Server Linux
Includes Nisse-SSL Trust Seal

Multi-Domain EV
Ideal for e-commerce and enterprise websites
Highest Level of Encryption
12/5 Expert Service
Unlimited Server Licenses
2048-bit encryption
30-Day Money Back Guarantee
Compatible with all leading web and mobile browsers
Server Linux
Includes Nisse-SSL Trust Seal

4.5
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Explore the benefits of choosing a multi-year plan on Nisse-SSL. Save time and money while ensuring long-term security and stability. With this strategic option, avoid frequent renewals and control your budget. Discover how the multi-year plan can improve your efficiency and protect your investment. Opt for premium services without the hassle of annual price increases. Choose a plan that suits your needs today and enjoy the benefits of financial stability and convenience.
Validation Requirements
This comprehensive guide explores the importance of multi-domain SSL certificates for secure online communication. Learn about the various SSL validation types—Domain Validation (DV), Organization Validation (OV), and Extended Validation (EV)—and follow our step-by-step process to validate and issue your own multi-domain SSL certificate. From choosing a Certificate Authority to installing your SSL certificate correctly, this resource will help ensure your online business is safeguarded, enhancing both security and user trust.
Domain Validated SSL certificates are the most basic and easiest to validate using a single step to verify the person or organization who owns the registered domain(s).
To complete the validation, the domain owner must prove that they own the fully qualified domain name or names that were submitted with the order.
The easiest and preferred method is completing the verification with email-based authentication. Using this preferred method, we will send an email to the WHOIS registrar email address asking you to verify that you purchased a DV certificate. Once you positively respond to our email, the requirement is considered satisfied and the certificate can be issued within minutes of a completed order.
As an alternative to the WHOIS registered email, we can send the authentication email to one of five pre-approved email addresses associated with the website domains. The five pre-approved addresses are:
- Admin@name-of-site.com
- Administrator@name-of-site.com
- Webmaster@name-of-site.com
- Hostmaster@name-of-site.com
- Postmaster@name-of-site.com
If the email Domain Validation does not work for your particular situation, there are alternative methods.
- File-Based Authentication – we will provide you with a text file that you will need to upload to the root directory of your website. We will then verify your websites via HTTP or HTTPS.
- CNAME-Based Authentication – we will provide you with two unique hash values (these are MD5 and SHA1). You, in turn, must enter them in your CNAME DNS record.
Organization Validated SSL certificates for multiple domains require more validation than Domain Validated ones and provide more trust. With an OV certificate, we confirm the business associated with the domain names is registered and legitimate by checking details such as the company name, location, address, and incorporation or registration information. This makes the certificate a more suitable option for public-facing websites that represent companies or organizations. OV’s are usually used by corporations, governments and other entities that want to provide an extra layer of confidence to their website visitors. Organization Validation requirements for an organization include:
- Domain Ownership/Authentication
- Organization Authentication
- Locality Presence
- Telephone Verification (Organization phone number found on an online database
- Final Verification phone call
For legitimate organizations, this process goes smoothly and quickly. Remember, an OV certificate differentiates legitimate businesses from the pretenders—including scammers and hackers.
An OV SSL certificate for an individual requires the identity and address to be validated on the certificate. Individual identity is verified by the applicant providing one of the following documents:
- Legible copy of a government-issued photo ID such as a valid driver’s license, passport, military ID, or National ID
- Copy of a recent major utility bill (i.e. power bill, water bill, etc.)
- Copy of a bank or credit card statement
The Extended Validation certificate has very strict industry guidelines that our validation specialists make as simple as possible with minimal action required from you. This level of security is recommended for sites that obtain personal information from users, such as eCommerce websites.
The validation of your organization can be completed using 1 of 3 methods:
- DCV email
- CNAME
- HTTP(S) challenge
Anticipate a telephone call to the main business phone number listed on the subscriber agreement to verify the signature, authority to sign and signer’s title. If any additional actions are required a validation specialist will reach out to you via email. The telephone call to verify the authenticity of the order and signer listed on subscriber agreement can not be made to a direct phone number or cell phone unless the number can be validated.
Tips When Validating
- Sole proprietorship / sole trader and some partnerships require a principal individual in the organization to be verified.
- All EV certificates must have the legal name. If a tradename/DBA is verified, the certificate will be listed with the tradename and legal name.
- In the case of a sole trader the legal name is the owner/principal name.
- No certificate can be issued to the tradename/DBA name only.
- Use the address where the organization conducts business. Do not use PO Box, Care of, mail stop/forwarding, virtual office or a registered agent address.
- If the Validation Specialist is not able to verify your organization, you will be contacted with options on how to resolve any outstanding issues.
Discover the benefits of Multi-Domain SSL Certificates, which allow website owners to secure multiple domains with a single certificate. Learn how the combination of Multi-Domain and Wildcard SSL enhances security for both primary domains and their subdomains, simplifying SSL management and reducing costs. This comprehensive approach keeps your digital assets protected and compliant with evolving security standards, making it ideal for businesses that manage multiple, related websites.
Multi-domain SSL certificates are versatile security tools that enable website owners to secure multiple domains with a single certificate. This feature is particularly beneficial for businesses managing a range of websites, allowing them to streamline their security processes and reduce costs associated with obtaining individual SSL certificates for each domain.
Wildcard SSL certificates extend the functionality of standard SSL by securing a primary domain and all of its subdomains. For instance, a wildcard certificate for *.example.com will safeguard example.com, blog.example.com, and shop.example.com, simplifying SSL management. This extensible feature can be particularly advantageous when combined with multi-domain SSL configurations, providing enhanced flexibility and efficiency.
By leveraging both multi-domain capabilities with wildcard features, organizations can secure multiple related domains and their subdomains seamlessly. This dual functionality not only simplifies the management of SSL installations but also enhances overall site security. Furthermore, it enables organizations to adapt to changes in their web structure without the need for additional certificates, ensuring that all their digital assets remain protected and compliant with the latest security standards.
Discover the benefits of a multi-domain SSL certificate and how Nisse-SSL can simplify your website security management. Secure multiple domains under a single certificate to increase user trust and efficiency. Nisse-SSL offers centralized management, customized options, and excellent customer support, ensuring solid protection for your online assets. Whether you are a small business or a large organization, find the right SSL solution to meet your unique needs and keep your websites safe.
Nisse-SSL offers a seamless approach to managing multi-domain SSL certificates. With Nisse-SSL, you benefit from centralized management of your SSL assets, ensuring that all your domains are reliably protected. The convenience of this service greatly improves the security posture of your website, while promoting user trust. In addition, Nisse-SSL offers excellent customer support, helping you quickly resolve any issues that may arise, further establishing the credibility of your domains.
When selecting a multi-domain SSL certificate from Nisse-SSL, it’s essential to assess your unique needs. Consider the number of domains you intend to secure and the level of encryption required. Nisse-SSL offers various options tailored to different needs, each promising robust protection for your online assets. Ultimately, the right choice depends on your organization’s size, industry, and specific security protocols.