To choose an email deliverability consultant, compare candidates on how they diagnose root causes, the data they work from, their experience with your volume and ESP, and how they hand the program back to your team. High-volume SaaS senders and VP Marketing should ask for a written audit method, named case studies with before and after inbox placement, and a clear plan for ongoing monitoring.
MailSoar is an international email deliverability consultancy specializing in inbox placement, sender reputation, email authentication and email infrastructure. This guide shares the criteria we would use ourselves if we were hiring a deliverability partner.
Meet MailSoar at SAAS NORTH 2026. We are exhibiting at Canada’s SaaS and AI conference on November 4 and 5, 2026, at the Rogers Centre in Ottawa. Visit us at booth #A30 to talk through your deliverability questions with our experts, or book a meeting with us in advance.
When does a SaaS company need a deliverability consultant?
Most SaaS teams call in outside help when email starts costing them revenue, not before. These are the signals we see most often in high-volume senders:
- Open rates drop by several points with no change in content or audience.
- Gmail or Microsoft starts placing marketing or product emails in spam or Promotions.
- Transactional emails (sign-ups, password resets, invoices) arrive late or not at all.
- Your domain or IP appears on a blocklist such as Spamhaus or SURBL.
- You are about to change ESP, add a sending domain, warm up a new IP or multiply your volume.
- Google Postmaster Tools shows a falling domain reputation or a spam rate above 0.3%.
If two or more apply, an external audit usually pays for itself faster than internal trial and error. Read also 10 signs you need to consult an email deliverability expert.
8 criteria to compare email deliverability consulting services
The table below is the grid we recommend for any shortlist. Score each consultant from 1 to 5 on every line.
| Criterion | What good looks like | Question to ask |
|---|---|---|
| Diagnostic method | A written audit covering authentication, infrastructure, reputation, list health and content, ending in a prioritized action plan | Can you show me an anonymized audit report? |
| Data sources | Google Postmaster Tools, Microsoft SNDS, seed and panel inbox tests, ESP logs, bounce codes | Which data will you need access to, and which will you bring? |
| Volume experience | References at your scale, from a few million to 50M+ emails a month | What is the largest program you have recovered? |
| ESP and stack coverage | Hands-on work in your ESP (Braze, Iterable, Customer.io, Klaviyo, Salesforce, HubSpot) and in your DNS | Have you worked in our ESP before? |
| Mailbox provider expertise | Specific playbooks for Gmail, Microsoft, Yahoo and regional providers in your markets | How do you handle a Microsoft block versus a Gmail spam issue? |
| Proof | Named case studies with before and after inbox placement and open rates | Which client in our industry can I talk to? |
| Scope after the audit | The consultant implements fixes with your team, not only recommendations | Who does the work after the audit, you or us? |
| Monitoring and handover | Ongoing alerts, a reporting cadence, and training so your team owns the program | What happens when the mission ends? |
How should a VP Marketing compare deliverability consultants?
A VP Marketing does not need to judge DNS records. The job is to check that the consultant ties deliverability to business outcomes and can work with your CRM, product and engineering teams. Five questions separate strong candidates quickly:
- Which metrics will you report to me each month, and how do they connect to pipeline or revenue?
- What will my team need to change, and how much of their time will the mission take?
- How do you prioritize when marketing, product and transactional emails share the same domain?
- What results did you reach for a company of our size, and in how many months?
- How do you make sure the problem does not come back after you leave?
Enterprise CRM managers should add one more: how the consultant works inside governance rules, such as access rights, change approval and security reviews.
Red flags
- A guaranteed inbox placement rate before any audit.
- A tool subscription presented as the solution, with no human analysis.
- No named references, or only references outside your industry and volume.
- Recommendations limited to content tips (spam words, emojis) when the problem is reputation or infrastructure.
- No plan for monitoring once the fix is delivered.
A 5-step selection process for high-volume SaaS senders
- Gather your baseline. Export 90 days of opens, clicks, bounces and complaints by mailbox provider, plus Google Postmaster Tools and Microsoft SNDS data.
- Write a one-page brief. Monthly volume, ESPs, sending domains, main symptoms, and the deadline that matters (a launch, a migration, Black Friday).
- Shortlist two or three consultants and score them with the 8 criteria above.
- Ask each one to read your baseline. A strong consultant will form first hypotheses in a 30-minute call, before any contract.
- Start with a scoped audit. Agree on the deliverables, the timeline and the success metrics (inbox placement by provider, open rate, spam rate) before moving to implementation and monitoring.
How MailSoar works with SaaS and marketing teams
MailSoar organizes every mission around four services, so you can start where your program needs it:
- Find: a deliverability audit that identifies the root cause and ends with a prioritized action plan.
- Fix: recovery, with our experts implementing the plan alongside your team until emails are back in the inbox.
- Grow: scaling your email program without hurting deliverability.
- Run: ongoing monitoring that catches issues before they cost you revenue.
Our 25 senior experts have worked with 500+ companies in 20+ countries, and MailSoar is rated 4.9/5 on 203 verified Trustfolio reviews. Three results from high-volume senders:
| Client | Context | Result |
|---|---|---|
| Agicap | B2B fintech SaaS, 5M emails a month in several countries | Microsoft inbox placement from 60% to 98% in 9 months |
| Swile | HR tech scale-up on Salesforce Pardot, 5M emails a month | Inbox placement from 50% to 95%, opens from 20% to 35% |
| GetFlex | Consumer fintech app, 50M+ emails a month | Inbox placement from 75% to 99%, opens up 70% |
More results on our client reviews page.
FAQ
Not sure where your program stands? Come and see us at SAAS NORTH in Ottawa on November 4 and 5, or book a meeting with a MailSoar deliverability expert.



