The Cold Email Agency

    Email Deliverability Services That Get You Back in the Inbox

    If your cold email is landing in spam, the copy is rarely the problem. We audit authentication, reputation, infrastructure and warm-up, fix the cause, and prove placement with seed testing.

    Book a Deliverability Audit +44 207 183 3436

    Sound familiar?

    Open rates collapsed overnight with no change to your copy
    Replies dried up but sends and bounces look normal
    Gmail delivers, Outlook and Microsoft 365 silently drop you
    Your domain shows up on Spamhaus, Barracuda or a Microsoft block list
    Warm-up scores look fine but real prospects never respond
    Your main domain got burned by a previous agency or tool

    What the deliverability audit covers

    Authentication

    SPF, DKIM, DMARC and BIMI records checked, corrected and aligned across every sending domain.

    Domain & IP reputation

    Blacklist checks, Google Postmaster and Microsoft SNDS reputation, plus history on any inherited domain.

    Infrastructure design

    Secondary domain strategy, inbox count, sensible per-inbox volume caps and rotation — never your main domain.

    Warm-up & ramp

    A real warm-up schedule rather than a switch you flip, with volume ramped against reply signal.

    Content & spam signals

    Link handling, image weight, trigger phrases, unsubscribe mechanics and thread structure.

    Placement testing

    Seed testing across Gmail, Microsoft 365, Outlook and common UK business hosts before a real send.

    What you end up with

    Inbox placement restored to 90%+ on seed tests
    Bounce rate under 2% on every verified list
    Removal from blacklists, with the cause fixed rather than papered over
    A sending architecture that survives scaling to 10,000+ sends/month
    Your primary domain protected and kept out of the send pool

    Deliverability monitoring is included at no extra cost inside every fully-managed cold email service retainer — see cold email agency pricing.

    Deliverability FAQs

    What does an email deliverability consultant do?+

    An email deliverability consultant diagnoses why your messages are landing in spam or being dropped entirely, then fixes the underlying causes: authentication records, domain and IP reputation, sending infrastructure, warm-up, list hygiene and message content. The output is inbox placement you can measure, not general best-practice advice.

    How much do email deliverability services cost?+

    A one-off deliverability audit and remediation typically runs £750–£1,500 depending on how many domains and inboxes are in play. Ongoing monitoring is included free inside any fully-managed cold email retainer, which starts at £1,500 per month.

    How long does it take to recover a burned domain?+

    If the domain is blacklisted or has a poor reputation history, plan for 3–6 weeks: delist, correct authentication, pause sending, then re-warm slowly. In most cases the faster and safer route is to move sending onto fresh secondary domains and retire the burned one from outbound entirely.

    Should I send cold email from my main company domain?+

    Keep business-critical and outbound sending reputation in mind when choosing domains. A dedicated sending domain or subdomain may help separate mail streams, but it is not a substitute for correct SPF, DKIM and DMARC configuration, permission checks, list quality, low complaints and monitoring. A domain change is not guaranteed to restore inbox placement.

    Do warm-up tools alone fix deliverability?+

    No. Warm-up networks improve engagement signals but cannot correct broken authentication, bad list quality, an over-loaded inbox, or content that trips spam filters. Warm-up is one input among six — treating it as the whole solution is why so many campaigns plateau.

    Technical diagnosis before more volume

    A practical email deliverability audit checklist

    An apparent drop in replies can come from poor targeting, changes to domain authentication, reputation issues or a mailbox provider's filtering. An audit should separate these causes rather than promising that another warm-up subscription will solve them.

    01

    Verify identity, alignment and DNS

    Inspect SPF and DKIM results, DMARC alignment with the visible From domain, MX records, reverse DNS where relevant, and TLS transport. Check that forwarding or shared sending infrastructure is not breaking authentication. Google's current guidance calls for SPF or DKIM from all Gmail senders and more stringent SPF, DKIM and DMARC requirements for high-volume senders.

    • SPF / DKIM / DMARC authentication and alignment
    • Sending domain and mailbox configuration
    • Bounce codes, blocklists and provider-specific deferrals
    02

    Investigate what changed before the drop

    Compare recipient segments, send cadence, complaint signals, hard bounces and reputation indicators before and after the issue appeared. Check whether a new data supplier, a sudden volume increase or a change in copy coincided with the decline. When bounce or deferral rates rise, pause or reduce sending while the underlying cause is isolated.

    • Volume ramp and sending history
    • Invalid addresses, unsubscribes and complaints
    • Reputation and inbox placement by provider
    03

    Set measurable recovery and protection rules

    Separate diagnostic tests from normal production sends and document which domains and inboxes may be used. Monitor delivery and accepted replies by provider; do not confuse provider acceptance with inbox placement. An improvement plan should state what will be rechecked, who owns remediation, and when sending can safely resume.

    • Clear before-and-after test methodology
    • Suppression and list verification safeguards
    • Actions and owners for ongoing monitoring

    Technical sending requirements and thresholds can change. See Google's published sender requirements for the current baseline.

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    Get a deliverability diagnosis

    Send us your domains. We'll tell you what's broken, what it will take to fix, and whether it's worth fixing at all — in one call.

    Book a Deliverability Call