SpamFactor compared with other spam filters

There are many hosted spam filters. Here is how SpamFactor compares with five of them on what most small businesses ask about: what it costs, where your mail goes and what the filter does with it.

SpamFactor is our own product. The facts about the others come from their own websites, checked on 10 October 2026. Prices exclude VAT and can change, so check the provider's website before you decide. Spotted something out of date? Let us know at info@spamfactor.com.

SpamFactor SpamHero MX Guarddog SpamExperts N-able Mail Assure Hornetsecurity
Pricing €9.99 per domain per year, any number of addresses From $7 per domain per month (annual prepay, $5 in the first year), with a monthly message limit per plan $0.25 per address per month On quote, sold through web hosting companies On quote, sold through IT partners On quote, sold through IT partners
Example: one domain with 10 addresses, per year €9.99 $84 (Lite, after the first year) $30 Not stated Not stated Not stated
Where your mail is filtered Servers in the EU Not stated Not stated Not stated Not stated Own data centres in Germany
Quarantine 30 days, release from the dashboard or a report by email 7, 15 or 30 days, depending on the plan Yes, with quarantine reports to every user Yes Yes Yes
Outbound filtering No, incoming mail only From the Standard plan No, incoming mail only Yes Yes Yes
Archiving No 7 to 30 days, depending on the plan No Yes Yes, long-term Available as a separate product
Apps for iPhone and Android Coming soon. The dashboard already works in the browser on your phone No app mentioned No app mentioned No, its quarantine app was discontinued in 2022 Not stated Not stated
API Yes, for administrators and resellers Yes No API mentioned Yes, with add-ons for cPanel, Plesk, DirectAdmin and WHMCS Yes Yes
Made for Small businesses, web developers and resellers Small and medium businesses Small businesses Web hosting companies and telecom providers Managed service providers (MSPs) Businesses, through IT partners

Sources: SpamHero, MX Guarddog, SpamExperts, N-able Mail Assure, Hornetsecurity. SpamExperts, Mail Assure and Hornetsecurity do not publish prices; ask a partner or your hosting provider for a quote. About the SpamExperts app: SpamExperts blog.

Where SpamFactor is different.

One price per domain

€9.99 per domain per year, whether it has two addresses or two hundred. No message limits and no counting mailboxes.

Filtered in the EU

Filtering, quarantine and logs run on servers in the EU, from a Dutch company you can call.

Every decision explained

The dashboard shows every message, including the refused ones, with every check that raised or lowered its score.

Release from your inbox

Reports by email on the days and times you choose, with a release link for every blocked message.

What SpamFactor does not do: filter outgoing mail, archive mail or offer email continuity. If you need those, one of the larger suites below is a better fit.

Which spamfilter should I pick?

SpamFactor

SpamFactor is a hosted filter for incoming mail from a Dutch company, run on servers in the EU. You pay €9.99 per domain per year, whatever the number of addresses or messages. The dashboard shows why every message was delivered or refused, and reports by email let you release blocked mail with one click. There is an API, and apps for iPhone and Android are coming soon.

Choose SpamFactor when you want good spam filtering for one or more domains at a fixed, low price, with your mail filtered in the EU and every decision visible, and you don't need outbound filtering or archiving.

SpamHero

SpamHero is a hosted filter from iSparks in the United States, priced per domain with unlimited addresses, like SpamFactor. The plans differ in message limits, quarantine and archive days, and the Standard plan adds outbound filtering. There is an API.

Choose SpamHero when you also want to filter outgoing mail, and you are fine with a monthly message limit and a price in US dollars.

MX Guarddog

MX Guarddog is a hosted filter for incoming mail, priced per address. It sends quarantine reports to every user and keeps mail for up to a week when your own server is down. Its website does not say where the servers are, and mentions no API or app.

Choose MX Guarddog when you have a domain with only a few addresses, so a price per address works out cheaper.

SpamExperts

SpamExperts, now part of N-able, filters incoming and outgoing mail and archives it. It is made for web hosting companies, with add-ons for cPanel, Plesk, DirectAdmin and WHMCS, so you usually get it through your hosting provider. Its mobile quarantine app was discontinued in 2022.

Choose SpamExperts when your hosting provider already offers it with your hosting package, or you are a hosting company that wants a filter built into cPanel or Plesk.

N-able Mail Assure

Mail Assure is the sister product of SpamExperts at N-able, made for managed service providers. Besides inbound and outbound filtering it offers long-term archiving, email continuity during an outage and an API.

Choose N-able Mail Assure when you are an MSP that wants one console for archiving, continuity and filtering for many customers, and you buy through a partner.

Hornetsecurity

Hornetsecurity is a German email security company with its own data centres in Germany. Its spam filter is part of a larger range that includes archiving, backup and security for Microsoft 365, sold through IT partners. Its control panel has an API.

Choose Hornetsecurity when you want a large suite from one vendor, beyond spam filtering, and you have an IT partner that sells and manages it.

Questions

Do I need a separate spam filter if I use Microsoft 365 or Google Workspace?
Not always. Both have a spam filter built in, and for many mailboxes that is enough. A separate filter helps when spam or phishing still gets through, when you want one place to see and release refused mail for several domains or customers, or when you want the filtering to happen on servers in the EU before mail reaches your provider.
Why is SpamFactor priced per domain instead of per mailbox?
Because the work is the same for every domain, whether it has two mailboxes or two hundred. You pay €9.99 per domain per year, without counting addresses or messages.
Does SpamFactor filter outgoing mail or archive mail?
No. SpamFactor only filters incoming mail, and it does not archive. If you need outbound filtering, archiving or email continuity, a larger suite such as SpamExperts, N-able Mail Assure or Hornetsecurity fits better.
Can I switch from another spam filter to SpamFactor?
Yes. You replace the MX records of the old filter with ours and let your mail server trust our servers instead. We set it up with you and check that mail flows correctly before you switch.

All questions and answers

Want to try it on one domain first?

Send us the domain you'd like to protect. We set it up with you and check that mail flows correctly before you switch the MX records.

info@spamfactor.com

Or use the contact form, or see pricing.