Gmail inbox placement fell from 77% to 52% in 2026
Email deliverability is changing, with notable shifts in how major providers like Gmail and Outlook handle incoming messages. According to Unspam's 2026 deliverability report, Gmail's inbox placement rate dropped from 77.3% in February to 51.7% by August, while Outlook's climbed from 41.2% in January to a May peak of 74.0%.
One caveat before the numbers: Unspam's data comes from senders who ran deliverability checks through its platform, a sample that skews toward senders already diagnosing a problem. The report states plainly that it does not represent all email worldwide, and it does not publish a sample size. Read these figures as directional signals about provider behavior, not as industry averages.
How has email deliverability changed for Gmail and Outlook in 2026?
Gmail and Outlook have taken divergent paths this year.
Month | Gmail | Outlook |
|---|---|---|
January | 73.7% | 41.2% |
February | 77.3% | 55.3% |
March | 74.2% | 65.5% |
April | 65.2% | 72.6% |
May | 69.7% | 74.0% |
June | 59.4% | 73.8% |
July | 61.2% | 66.5% |
August | 51.7% | 66.8% |
The crossover happened in April, when Outlook passed Gmail for the first time and never gave the position back. Gmail peaked in February and has fallen 25 points since. Outlook peaked in May at 74.0% and has since slipped roughly seven points, settling into the mid-60s through the summer — a rise followed by a plateau, not a steady climb.
These shifts highlight the importance of monitoring provider-specific trends rather than relying on blended averages, which can mask movements this large in both directions.
What factors influenced Gmail's deliverability drop?
Gmail changed how it handles non-compliant bulk mail in November 2025, answering it with temporary 4.7.x and then permanent 5.7.x SMTP errors rather than filtering it to spam. That shift from filtering to rejection means a failed requirement now increasingly shows up as a bounce rather than as poor inbox placement, and senders must meet compliance standards to avoid losing the message entirely.
Authentication trends add context, though not a proven cause. DMARC adoption fell from 59% of tested domains in 2025 to 48% in 2026, making it the only authentication signal to decline while SPF, DKIM, and reverse DNS all rose. The report does not attribute Gmail's placement drop to that decline, and neither should you — but a shrinking share of authenticated domains is worth watching in an environment where non-compliance now produces bounces.
Why did Outlook's deliverability improve?
Outlook's inbox placement rose sharply through the first half of the year, from 41.2% in January to 74.0% in May, then settled back to 66.8% by August. The improvement suggests Outlook's filtering algorithms or policies became more favorable to well-configured mail, though the mid-year plateau indicates the gains have stopped compounding.
Worth noting separately: sender-side HTML compliance improved across the board, from 23% in 2025 to 43% in 2026. That is a change in how senders build their mail, not an explanation for how Outlook filters it. Both trends are real; they are not the same story.
What should you do to improve email deliverability?
To address these changes, consider the following steps:
Segment your deliverability strategy by mailbox provider. Monitor Gmail and Outlook separately to identify specific trends and adjust your tactics accordingly.
Prioritize list hygiene and engagement tuning differently for Gmail versus Outlook. Regularly clean your email lists and focus on engaging content to maintain high deliverability rates.
Ensure compliance with DMARC and other authentication protocols. With Gmail now bouncing non-compliant bulk mail rather than filtering it, an authentication gap costs you the send, not just the inbox.
Adopt HTML best practices and improve subject line quality. Compliance in these areas has improved industry-wide, which means the bar for standing out has moved.
For a deeper dive into optimizing your email deliverability, explore Scalero's insights on Gmail deliverability triage and HTML design best practices.
Start by segmenting your strategy by provider. Focus on compliance, list hygiene, and engagement tuning, and track Gmail and Outlook as two separate programs rather than one blended number.
