ShieldMarc vs dmarcian
A straight comparison for UK MSPs deciding between the two.
dmarcian is one of the longest-running DMARC platforms and employs several of the protocol's original authors. It is a credible choice. Where ShieldMarc wins is per-domain economics, predictable billing, on-demand deep reasoning with Claude Opus 4.7 on top of our own threat model, and a UK-owned / EU hosted default. Figures below are from dmarcian's public pricing page at the time of this page's most recent review (April 2026). Verify directly at dmarcian.com/pricing.
Flat pricing beats step-function upgrades
dmarcian jumps from $24/mo (Basic, 2 domains, 100k messages) to $240/mo (Plus, 8 domains, 1M) to $600/mo (Enterprise, 15 domains, 5M). You outgrow a tier, you take a 10x jump. ShieldMarc Professional covers 25 domains for £49/mo annual and MSP covers 100 domain slots for £99/mo, with bucket expansion at £39.99/mo each.
Threat model + Claude Opus 4.7
Paid ShieldMarc plans run every DMARC report row through our proprietary threat model, then Claude Opus 4.7 reasons on top. dmarcian relies on its own tooling.
UK owned, EU hosted by default
ShieldMarc is a UK-based operation with EU hosted infrastructure and UK hosting available on request. dmarcian is US-based with global deployment, which means CLOUD Act exposure by default.
Pricing and plan limits (April 2026)
| Feature | dmarcian | ShieldMarc |
|---|---|---|
| Free tier | Personal: 2 domains, 1,250 messages/mo, 1 user | Starter: 1 domain, 10,000 messages, 18 free tools, AI explanations included |
| First paid tier | Basic: $24/mo ($239.88/yr, ~£19/mo), 2 domains, 100k messages/mo, 1 user | Professional: £49/mo annual, 25 domains, 5,000,000 messages/mo, 5 users |
| First-paid cost per domain | ~£9.50/domain/mo (2 domains) | ~£1.96/domain/mo (25 domains) |
| Top published tier | Plus: $240/mo ($2,388/yr, ~£188/mo), 8 domains, 1M messages/mo, 3 users | MSP: £99/mo annual, 100 domain slots, 20,000,000 messages/mo, unlimited users |
| Top-tier cost per domain | ~£23.50/domain/mo | £0.99/domain/mo (MSP at capacity) |
| Published Enterprise tier (non-bespoke) | Enterprise: $600/mo ($5,988/yr, ~£470/mo), 15 domains, 5M messages/mo | None: MSP + expansion buckets at £39.99/mo covers any volume or domain count on published pricing |
| Overage handling | Hit the message cap, upgrade to the next tier (often a 10x price jump) | No hard cap, 3-month grace, no surprise billing |
| Expansion pricing | Take the next tier | +50 domain slots and +5 million messages for £39.99/mo (published) |
| Enterprise tier purpose What actually triggers a custom quote | Triggered by volume cap on Plus. You effectively pay 10x to cross the 1M or 8-domain boundary. | Triggered only by formalised SLA, regional hardware hosting, EU-only AI routing, or specific compliance frameworks. Standard scale stays on published MSP + buckets. |
| Can you estimate your cost upfront? | Yes up to the published Enterprise tier, then no for anything above 15 domains / 5M messages. | Yes, for every standard case. Enterprise is only for compliance / hosting specifics. |
Features and depth
| Feature | dmarcian | ShieldMarc |
|---|---|---|
| Analysis engine Paid tiers only, on-demand only. We combine both. | In-house tooling only | Proprietary threat model + Claude Opus 4.7 |
| Automated AI background jobs | n/a | None. AI fires only when a user clicks |
| Subdomain policy (sp=) detection | Policy detected | sp= scored independently, weaker-than-p flagged as a distinct control failure |
| Lookalike domain scanning | Not included in published tiers | All plans |
| SSL, DNS, DNSSEC, MTA-STS, TLS-RPT, CAA monitoring | Partial | All included on paid tiers |
| Brand TLD grouping (MSP) | Not available | TLD variants count as one slot |
| Original research publication | Protocol documentation and blog | UK MSP DMARC Audit Q1 2026 (192 providers analysed) |
Data, hosting and privacy
| Feature | dmarcian | ShieldMarc |
|---|---|---|
| Company base | US-based | UK owned and run |
| Default hosting | Global, US-touching | EU hosted, UK hosted on request |
| PII stored | Standard SaaS profile | Minimal by design: account emails, audit log, rare RUF headers |
| Subject to US CLOUD Act | Yes | No (UK based, EU hosted) |
| Third-party certifications | SOC 2 | None held today; scaling target |
Conclusion
Where ShieldMarc has an edge
- Flat, predictable pricing. 25 domains for £49/mo annual, or 100 domains for £99/mo. No step-function jumps from £19/mo to £188/mo to £470/mo as you grow.
- 4x the message ceiling at mid-tier (5M vs dmarcian Plus's 1M) and 4x at top published tier (20M vs Enterprise's 5M).
- Paid-plan AI analysis combines our proprietary threat model with Claude Opus 4.7, on demand only.
- Full stack in one dashboard on paid tiers: DMARC, SPF, DKIM, SSL, DNS, DNSSEC, MTA-STS, TLS-RPT, CAA, domain expiry, uptime, lookalike.
- Subdomain policy (sp=) scored independently, weaker-than-p flagged as a distinct control failure.
- UK-owned, EU-hosted by default, UK hosted on request. No US CLOUD Act exposure.
- Original UK MSP DMARC Audit published with methodology and data; rare in this category.
Where dmarcian stacks up
- Several of the original DMARC RFC authors work at dmarcian. Unmatched depth on the DMARC standards side of the product.
- Over a decade of running DMARC at scale. Longer track record than ShieldMarc, which is early days.
- SOC 2 attestation today. ShieldMarc does not have one. If your procurement has it as a hard gate, dmarcian satisfies that and we will not.
- Enterprise-tier sender-management features like hosted SPF that dmarcian offers. ShieldMarc is deliberately focused on the DMARC, SSL and DNS fundamentals in early days; we do not ship hosted SPF or hosted BIMI today.
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