How to Audit Your Outsourced SDR Team's Email Infrastructure in 30 Minutes

You hired an outsourced SDR team to generate pipeline. They promised meetings, qualified leads, and consistent outreach volume. But here is the question most companies never ask: what is happening to your domain reputation while they send those emails?

When an outsourced team sends 500 to 2,000 emails per week from your domain (or a domain associated with your brand), a single infrastructure misstep can tank your deliverability for months. Bounced emails pile up, spam complaints accumulate, and suddenly your legitimate sales emails land in junk folders.

The good news: you can audit the critical elements of your outbound email infrastructure in 30 minutes. Whether you work with Vendisys or another outsourced GTM provider, this framework will help you verify that your sending reputation stays healthy.

Why This Audit Matters

Most companies discover email infrastructure problems reactively. A prospect mentions they never received your proposal. Your marketing team notices open rates dropped by 40%. Your domain ends up on a blocklist.

By then, the damage is done. Recovery takes weeks or months. A proactive 30-minute audit, done weekly or biweekly, catches problems before they cascade.

Here is what you are checking:

Authentication records (SPF, DKIM, DMARC)
Domain warming status and sending volume
Bounce rates and list hygiene
Reply handling and engagement signals
Overall domain reputation score

Let us walk through each step.

Step 1: Verify SPF, DKIM, and DMARC (5 Minutes)

These three DNS records are the foundation of email deliverability. Without them configured correctly, inbox providers will flag your outbound emails as suspicious.

SPF (Sender Policy Framework): This record tells receiving servers which IP addresses are authorized to send email on behalf of your domain. Run a lookup on your sending domain using MXToolbox or a similar tool. Confirm that every sending platform your SDR team uses is included in the SPF record.

Common problems to look for:

More than 10 DNS lookups in the SPF chain (this causes a “permerror” and SPF fails silently)
Missing entries for new outreach tools the team recently adopted
The “all” mechanism set to “~all” (softfail) instead of “-all” (hardfail) when you are confident in your sender list

DKIM (DomainKeys Identified Mail): This cryptographic signature proves the email was not tampered with in transit. Ask your outsourced team which DKIM selector they use, then verify the public key exists in your DNS. If they rotated keys recently, confirm the old key was not removed before all queued messages finished sending.

DMARC (Domain-based Message Authentication, Reporting, and Conformance): This policy tells receiving servers what to do when SPF or DKIM fails. Check your DMARC record for:

Policy set to at least “quarantine” (not “none” indefinitely)
A reporting address (rua) that someone actually monitors
Alignment mode that matches your sending setup

If your outsourced team cannot tell you the current state of these three records within five minutes of asking, that is a red flag.

Step 2: Check Domain Warming Status (5 Minutes)

If your outsourced SDR team set up new sending domains (which is best practice to protect your primary domain), those domains need proper warming before handling full volume.

Ask your team for:

The age of each sending domain (should be at least 2 to 4 weeks old before any outreach begins)
Current daily sending volume versus the warming schedule target
Whether volume ramped gradually (50 emails per day in week one, 100 in week two, and so on) or jumped abruptly

Red flags during this check:

A domain less than two weeks old sending more than 100 emails per day
Volume that doubled overnight rather than increasing by 20 to 30 percent daily
No dedicated warming period before outreach started
Sending domains that share no visual or textual connection to your brand (which can confuse prospects and trigger spam reports)

A reputable outsourced GTM partner like Vendisys will proactively share warming schedules and volume ramp plans without you needing to chase them for this information.

Step 3: Monitor Bounce Rates and List Hygiene (10 Minutes)

This is the step where most outsourced SDR arrangements quietly go wrong. Your team is sourcing contact lists, enriching data, and sending at volume. If their data hygiene is poor, your bounce rate climbs and inbox providers start throttling or blocking your domain.

What to check:

Pull the bounce rate from your team’s outreach platform (or ask them for a screenshot of their dashboard). Here is what healthy looks like:

Hard bounce rate: below 2% (ideally below 1%)
Soft bounce rate: below 5%
Overall deliverability rate: above 95%

If hard bounces exceed 3%, your list quality is a serious problem. This is where tools like Scrubby become essential. Running your prospect lists through email validation before sending catches invalid addresses, role-based emails, and disposable domains that would otherwise generate bounces.

Questions to ask your outsourced team:

What email validation tool do you use before sending?
How often do you re-validate existing lists?
Do you remove contacts after a hard bounce immediately or batch-process removals?
Are you scrubbing catch-all domains separately from verified addresses?

The validation step is non-negotiable. Every email that bounces is a data point telling Google, Microsoft, and other providers that you are sending to bad addresses, which is a hallmark of spam behavior.

Step 4: Audit Reply Handling and Engagement (5 Minutes)

Inbox providers track engagement signals beyond just opens and clicks. Reply rates, time-to-reply, and whether recipients move your emails to specific folders all factor into your sender reputation.

Check these elements:

Reply rate: healthy outbound campaigns see 3 to 8% reply rates (including negative replies). Below 1% consistently suggests your emails are not reaching inboxes or your messaging needs work.
Unsubscribe and spam complaint rate: should be below 0.1%. If higher, your targeting or messaging is off.
Positive reply handling: when a prospect responds, how quickly does your outsourced team route that reply to your sales team? Delays here kill deals.

For teams running multi-channel outreach that includes calendar-based touchpoints, tools like Kali can help track engagement from calendar invite outreach separately from email sequences. This gives you cleaner data on which channel drives actual responses.

Process check: Ask your outsourced team to show you their reply-handling workflow. You want to see:

Auto-detection of out-of-office replies (these should pause the sequence, not trigger follow-ups)
Negative reply detection (opt-out requests must be honored immediately)
Positive reply routing (should reach your AE within minutes, not hours)
Bounce processing (hard bounces removed from all active sequences instantly)

Step 5: Check Overall Domain Reputation (5 Minutes)

Several free tools give you a quick snapshot of your domain health:

Google Postmaster Tools: If you send to Gmail addresses (and you do), this is essential. Check your domain reputation rating (High, Medium, Low) and spam rate.
Microsoft SNDS: Similar data for Outlook and Hotmail recipients.
MXToolbox Blocklist Check: Verify your sending IPs and domains are not on any major blocklists.
Talos Intelligence: Cisco’s reputation lookup shows how their systems view your sending domain.

Run each of these checks. The entire process takes about five minutes once you have accounts set up. Bookmark them and make this part of your weekly routine.

Healthy indicators:

Google Postmaster shows “High” domain reputation
No blocklist appearances
Spam rate below 0.1% in Google Postmaster

Warning signs that require immediate action:

Domain reputation dropped from High to Medium or Low
Any blocklist appearance (even one)
Spam rate above 0.3%

Building This Into a Recurring Process

A one-time audit is useful. A recurring audit is what actually protects your brand. Here is how to make this sustainable:

Weekly (10 minutes): Check bounce rates and domain reputation score. These are your early warning system.

Biweekly (20 minutes): Run the full audit above. Verify authentication records have not changed unexpectedly and that warming schedules are on track.

Monthly (30 minutes): Review trends over time. Are bounce rates climbing? Is reply rate declining? These trends reveal slow-moving problems that a single snapshot might miss.

Quarterly: Request a full deliverability report from your outsourced team. This should include inbox placement rates by provider, authentication pass rates, and any incidents that occurred during the quarter.

What Good Outsourced Infrastructure Looks Like

When your outsourced SDR team is doing things right, you should see:

Dedicated sending domains that are properly warmed and aged
SPF, DKIM, and DMARC all passing with full alignment
Bounce rates consistently below 2%
Active list validation using a tool like Scrubby before every campaign launch
Reply routing that gets positive responses to your AEs within minutes
Transparent reporting with no metrics hidden behind “proprietary processes”
Proactive communication when something goes wrong (a blocklist appearance, a sudden bounce spike)

When to Escalate

If your audit reveals problems, here is the escalation framework:

Yellow flag (monitor closely): Bounce rate between 2 and 3%, domain reputation at “Medium,” or SPF record approaching the 10-lookup limit.

Orange flag (demand immediate action): Bounce rate above 3%, any blocklist appearance, DMARC set to “none” with no timeline to move to “quarantine,” or reply rate below 1% for three consecutive weeks.

Red flag (consider changing providers): Bounce rate above 5%, domain reputation at “Low,” multiple blocklist appearances, no email validation in place, or the team cannot produce basic deliverability metrics when asked.

The Bottom Line

Your outsourced SDR team is an extension of your brand. Every email they send affects your domain reputation, your ability to reach prospects, and ultimately your pipeline. A 30-minute audit gives you the visibility to catch problems early, hold your partners accountable, and protect the sending infrastructure that your entire outbound motion depends on.

Do not wait until your emails start landing in spam. Run this audit today, schedule it as a recurring task, and make email infrastructure health a standing agenda item in your next check-in with your outsourced team.