Deliverability Guide

Deliverability is whether your emails land in the inbox or the spam folder. It's the single biggest factor in whether your email marketing actually works. Here's everything you need to know.

The Three Things That Matter Most

1. Authenticate Your Domain

Email authentication proves to inbox providers (Gmail, Outlook, Yahoo) that you're a legitimate sender, not a spammer pretending to be you. You need three DNS records:

SPF — tells inbox providers which servers are allowed to send email from your domain.

v=spf1 include:sendgrid.net ~all

(Adjust the include based on your email provider.)

DKIM — adds a cryptographic signature proving the email hasn't been tampered with. Set this up in your email provider's dashboard — they'll give you a DNS record to add.

DMARC — ties SPF and DKIM together and tells inbox providers what to do with emails that fail authentication.

v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com

tip

Start with p=none (monitoring only). Once you're confident everything's set up correctly, move to p=quarantine and eventually p=reject.

If this feels technical, ask whoever manages your domain's DNS to help. It's a one-time setup that dramatically improves your deliverability.

2. Keep Your Lists Clean

Bad addresses destroy your sender reputation faster than anything else.

Do:

• Remove contacts who haven't opened anything in 6+ months
• Use suppression lists — Score CRM automatically handles bounces and complaints
• Validate email addresses against a verification provider to catch invalid, disposable, and risky addresses before you send
• Let Score CRM's automatic suppression do its job

Don't:

• Buy or rent email lists (high bounce and complaint rates guaranteed)
• Re-add suppressed contacts without a legitimate reason
• Ignore rising bounce rates

Healthy benchmarks:

Metric	Healthy	Needs Attention	Danger Zone
Bounce rate	Under 2%	2–5%	Over 5% — stop and clean your list
Complaint rate	Under 0.1%	0.1–0.3%	Over 0.3% — inbox providers may block you

3. Send Content People Want

The best technical setup in the world won't help if people don't want your emails.

Subject lines:

• Keep them under 60 characters
• Avoid ALL CAPS and excessive punctuation (!!!)
• Don't overuse spam trigger words ("FREE!!!", "ACT NOW", "LIMITED TIME")
• Be honest — the subject should match the content

Email content:

• Keep a good balance of text and images (don't send image-only emails)
• Avoid URL shorteners (spammers love them, so spam filters hate them)
• Include your physical mailing address (legally required in most countries)
• Don't go overboard with links

Unsubscribe link:

• Always include {{unsubscribe_url}} — it's required by law (CAN-SPAM, GDPR)
• Make it easy to find, not hidden in tiny grey text
• Score CRM processes unsubscribes automatically and immediately

Warming Up a New Domain or Provider

If you're sending from a new domain or just connected a new email provider, don't blast your full list on day one. Inbox providers are suspicious of new senders with sudden high volume.

Warm-up schedule:

Day	Emails Per Hour	What to Watch
1–2	500	Bounce rate, any immediate blocks
3–4	1,000	Complaint rate
5–7	2,500	Open rates, spam folder placement
Week 2	5,000	All metrics stabilizing
Week 3+	Increase gradually	Continue monitoring

Use Score CRM's throttling feature in campaign settings to control your sending speed. See Delivery Settings.

Tips during warm-up:

• Send to your most engaged contacts first (they're most likely to open, which builds reputation)
• If bounce or complaint rates spike, slow down immediately
• Maintain a consistent schedule — don't send 500 one day and 50,000 the next

Sending Best Practices

• Be consistent — send on a regular schedule. Sudden volume spikes trigger scrutiny from inbox providers.
• Segment your audience — send relevant content to targeted groups. Recipients who find emails relevant don't complain.
• Target engaged contacts — for important sends, use a segment like "opened in the last 60 days" to improve engagement metrics.
• Use custom tracking domains — your own branded domain is more trusted than a shared one.
• Keep image weight low and avoid image-only emails — large or heavy messages are slower to load and carry a higher spam-filter risk. Always set alt text for recipients who block images. Upload images directly instead of embedding them — see why hosted images are safer than embedded ones.

When Things Go Wrong

Emails Landing in Spam

1. Check authentication — SPF, DKIM, DMARC all set up and passing?
2. Review content — anything that looks spammy? Run your email through a spam checker.
3. Check your reputation — is your sending IP or domain on a blacklist? Use tools like MXToolbox.
4. Reduce volume — slow down and warm up again.
5. Improve targeting — send only to contacts who've engaged recently.

Open Rates Suddenly Dropped

1. Check bounce rates — if bounces spiked too, you might be getting blocked by a major inbox provider.
2. Verify tracking — is your tracking pixel working? Send yourself a test.
3. Consider Apple Mail — Apple Mail Privacy Protection can make open tracking unreliable.
4. Check the spam folder — send a test to Gmail, Outlook, and Yahoo accounts and check where it lands.

Bounce Rates Spiked

1. Pause sending immediately — continuing to send to bad addresses makes things worse.
2. Clean your list — remove invalid and old addresses.
3. Check for blacklisting — use MXToolbox or similar tools.
4. Resume slowly — send smaller batches and monitor closely.

Metrics to Watch After Every Send

Metric	Target	If Below Target
Delivery rate	Over 98%	Check authentication, clean your list
Open rate	15–25%+	Better subject lines, send to engaged contacts
Click rate	2–5%+	Improve content, make CTAs more compelling
Bounce rate	Under 2%	Clean your list, verify addresses
Complaint rate	Under 0.1%	Improve targeting, make unsubscribe easier

Review these in your Campaign Reports after every send. Trends matter more than individual numbers — watch for things getting worse over time.