A senior deliverability consultant, not a ticket queue. Bring what you are seeing (collapsing opens, replies landing in spam, a blacklist listing, a migration gone wrong) and leave the call knowing the most likely root causes and what happens next.
Reported across our client portfolio.
*After a full audit and remediation, Formula Inbox clients see inbox placement rates above 90%, based on seed list tests that reflect their ideal customer profile.
Calls are with a senior consultant. No sales script. If we are not the right fit, we will say so.
Loading...
Prefer to start with data? Get the free placement test first.
We ask what changed and when, because most crises have a start date and a trigger.
We look at your authentication, blacklist status, and sending setup for the obvious failure points.
We tell you what we think is causing it, what we would check next, and whether you need us or can fix it yourself.
Complimentary Inbox Placement Test: seed messages across the four largest spam filters, nine business email providers, and 18 free email providers, with DNS authentication and blacklist reporting.
Comprehensive Audit: we review the entire sending environment and identify root causes.
Remediation Roadmap: a detailed, actionable plan with the exact steps to fix each issue.
Implementation: we execute the infrastructure changes and content adjustments.
Ongoing Support and Monitoring: placement monitoring, reputation management, and error resolution.
Your existing ESP and email programs stay. What changes is the infrastructure, authentication, and practices that decide whether your email lands.
One-time engagement
Starting at $2,499
Find out exactly why your email is missing the inbox. We review authentication, placement, reputation, and blacklists, then hand you a written report with the fixes in priority order. Remediation is not included. After the audit, we recommend three months of monitoring and support, or remediation work can be scoped separately at a fixed price. See the full service page.
What’s included
One-time project
Starting at $999
Stand up sending infrastructure that is built to land. We configure domains, mailboxes, DNS, and your ESP, then warm everything to a measured baseline before you scale volume. See the full service page.
What’s included
Monthly retainer
Starting at $749/month
Keep placement high after the fixes are in. We monitor inbox rates and reputation, catch problems before they cost you replies, and give you one deliverability manager who knows your setup. See the full service page.
What’s included
Engagements are scoped per client. Book a call and we will tell you what fits.
Staffing and Recruiting Firm
A staffing and recruiting firm's Microsoft 365 mail went from 100% spam to 100% inbox in seven days after a false-positive phishing classification blocked new mail to established contacts. Overall inbox placement rose from 75% to 95%.
Read case studyUS Staffing Firm (Government Sector)
A US staffing firm serving government clients recovered after a DNS compromise that produced 28,000 fake pages and a Gmail 550-5.7.1 ban. Delivery error rate fell from 100% to 0% within days.
Read case studyIndependent Book Publisher (Shopify + Klaviyo)
An independent book publisher on Shopify and Klaviyo recovered from a 30,000-profile list-bombing attack that had driven bounce rates to about 30%. Campaign bounce rates fell back under 1%, open rates reached 62% to 69%, and the engaged audience recovered from about 300 to 550 to 600 readers per send.
Read case studyVP of Sales, Professional Services · via Upwork
Formula Inbox is terrific. We experienced a significant decline in our email response rate and spent weeks trying to figure it out. I did a one-hour consultation with Formula Inbox. They ran a series of tests and identified the problem and recommended several steps we need to take to correct it.
Owner, Independent Book Publisher · via Upwork
Formula Inbox was very helpful in helping me understand and unravel a list bomb attack and a whole set of deliverability issues. I plan to work with them again if I have any future issues.
VP of Operations, Marketing Agency · via Upwork
Amazing consultation! Very knowledgeable. On a completely different level than other deliverability conversations we've had. If you need somebody for SERIOUS deliverability and email infrastructure you're in good hands.
Yes. We are ESP-agnostic by design, and recommendations are tailored to your existing stack, not steered toward one platform.
No. Formula Inbox is a services practice. You work directly with a senior deliverability consultant. There is no SaaS platform or login.
It sends seed messages across the four largest spam filters, nine business email providers, and 18 free email providers, and reports DNS authentication status and active blacklist entries.
Yes. We treat cold, marketing, and transactional sending as three distinct programs with separate sending infrastructure.
No. Results depend on factors outside any consultant's control, such as list quality, recipient engagement, and provider policy changes. We find and fix the root causes of your problem. Ongoing monitoring is available as a separate service.
An audit takes 7 to 10 business days from when we receive access to your systems to the review call.
