A complete reference for inbox placement. Covers authentication setup, warmup strategy, spam filter avoidance, and sending volume management, with specific guidance on how Reach handles each area automatically.
Sender Policy Framework (SPF) is a DNS record that tells receiving mail servers which IP addresses are authorized to send email on behalf of your domain. Without a correctly configured SPF record, your messages look suspicious to email providers. A missing or misconfigured SPF record is one of the most common reasons legitimate cold email ends up in spam.
DomainKeys Identified Mail (DKIM) adds a cryptographic signature to your outgoing messages. This signature allows receiving servers to verify that the message was genuinely sent by your domain and was not altered in transit. Think of it as a tamper-evident seal on every email you send. Google, Microsoft, and Yahoo all check for DKIM before deciding inbox placement.
Domain-based Message Authentication, Reporting, and Conformance (DMARC) builds on SPF and DKIM by specifying what receiving servers should do when authentication checks fail. A DMARC policy set to reject or quarantine protects your domain from being spoofed. It also generates aggregate reports so you can monitor authentication failures across your domain.
Beyond SPF, DKIM, and DMARC, a fully hardened domain also configures MTA-STS to enforce TLS encryption for inbound delivery, TLS-RPT to receive reports on failed TLS connections, and BIMI to display your brand logo in supported inboxes. These records signal to ISPs that your organization takes email security seriously and contribute positively to your sender reputation.
Monitoring DMARC aggregate reports manually is time-consuming and error-prone. Skysnag Comply automates the entire process: it parses aggregate reports from every ISP, identifies unauthorized senders using your domain, and provides the visibility needed to safely advance your DMARC policy from none to quarantine to reject without disrupting legitimate mail flows.
Skysnag Comply: Automated DMARC Enforcement
Skysnag Comply gives you full visibility into every sender using your domain, automated aggregate report parsing, and a guided path from p=none to p=reject without disrupting legitimate email. It also monitors and enforces MTA-STS, TLS-RPT, and BIMI records from a single dashboard.
Reach integrates with Skysnag's domain authentication engine to scan your sending domains automatically. Before any campaign launches, Reach checks SPF alignment, DKIM key validity, DMARC policy configuration, MTA-STS, and TLS-RPT records. If an issue is detected, you receive an actionable alert before a single email is sent.
Spam filter algorithms have become sophisticated enough to evaluate intent, not just keywords. That said, certain patterns still reliably trigger filtering: excessive capitalization, promotional language like 'free', 'act now', or 'limited time', overly formatted HTML emails, and emails with too many images relative to text. Cold email should read like a professional letter from one person to another.
Your first email in a sequence should contain no more than one or two links. Heavy use of images, tracking pixels, and HTML formatting increases the probability of spam classification. Plain-text or lightly formatted emails consistently outperform rich HTML in deliverability tests across major email providers.
Generic, impersonal messages are flagged by both spam filters and human recipients. Reach's merge field system allows you to include recipient name, company name, industry, role, and any custom variable from your contact records. Every email in your sequence should feel like it was written specifically for the person receiving it.
Processing opt-outs immediately is both a legal requirement under CAN-SPAM, GDPR, and CASL, and a critical sender reputation factor. Reach processes unsubscribe requests and opt-out replies in real time. Contacts who opt out are suppressed across all sequences automatically and permanently.
Newly warmed accounts should begin at 20 to 50 sends per day and increase gradually over several weeks. Jumping to high volume before your account has established reputation is the fastest way to earn a spam designation. Reach enforces smart daily limits on new accounts and provides a recommended ramp schedule.
Sending your entire daily volume in a single burst is a behavioral signal associated with bulk spam operations. Reach distributes your outgoing messages across business hours in the recipient's time zone, simulating natural human sending patterns. This dramatically improves deliverability compared to batch sends.
A hard bounce rate above 2% will damage your sender reputation with every major ISP. Reach validates email addresses before sending using syntax checks, domain MX record verification, and SMTP verification where available. Invalid contacts are suppressed before they can affect your campaign's deliverability metrics.
For teams that need to send at enterprise scale, Reach supports connecting multiple sending accounts and rotating sends intelligently across them. Volume is distributed to keep each individual account within safe limits while your aggregate output scales to match your pipeline.