Based on aggregate Mailblast campaign data, the quarterly open rate for Amazon SES marketing sends has climbed from 14.6% (2023 Q1) to 18.9% (2026 Q2), a 4.3-point gain. The peak quarter was 2025 Q1 at 20.3%. This post walks through the trend, the two industry events that shaped it (Apple Mail Privacy Protection from 2021 and Gmail/Yahoo bulk sender enforcement from February 2024), and what the numbers mean for setting open-rate expectations on Amazon SES.
The headline observation: open rate as a measured metric has gotten more favourable across the period, but interpreting it as "deliverability has improved" requires care. Multiple confounding effects shape what shows up in the dashboard.
The 14-Quarter Open Rate Trend
The aggregate open rate climbed from 14.6% (2023 Q1) to 18.9% (2026 Q2), a 4.3-point gain across 14 quarters of marketing email through Amazon SES. The trend stair-steps up through 2023 and early 2024, peaks at 20.3% in 2025 Q1, then settles into a 17.6-19.0% band. Three distinct phases are visible in the quarterly data:
- Phase 1 (2023): open rates climb gradually from 14.6% to 16.7% across the year. This is the slow tail of post-pandemic email engagement recovery.
- Phase 2 (2024): sharp step up, especially after Q1. The 2024 Q4 quarter hits 19.4%. The most plausible driver is Gmail and Yahoo's February 2024 bulk sender enforcement (Google, 2026), which pushed lower-quality senders out of the ecosystem.
- Phase 3 (2025-2026): open rates oscillate in a 17.6-20.3% band, with the 2025 Q1 peak followed by gradual normalisation back to ~18-19%.
The Q1 2025 peak at 20.3% is the highest single quarter in the data. The most plausible interpretation: 12 months after Gmail and Yahoo enforcement, the SES sender population had completed its compositional shift toward higher-quality operators, and recipient engagement reflected that. The subsequent 2025 normalisation marks the boundary of how much sender-quality improvement can lift aggregate open rate before audience-side limits dominate.
Apple Mail Privacy Protection: The Open Rate Inflation Effect
Apple launched Mail Privacy Protection in September 2021 (Apple, 2026). MPP pre-fetches images in email messages when the recipient uses Apple Mail or any Apple-relayed inbox, including iCloud Mail. The mechanism: every message receives an image pre-fetch from Apple's relay servers, which causes the sending platform to register an "open" regardless of whether the recipient actually opened the message.
The effect on aggregate open rate measurement is large and structural. Public deliverability analyses have placed the MPP-driven inflation in the range of several percentage points for senders with significant Apple audiences. The 2023-2026 SES data here cannot disentangle MPP-inflated opens from genuine engagement growth; both effects compound, and we lack the per-recipient client telemetry to separate them.
Two practical implications:
- Open rate is no longer a reliable engagement metric on its own. A sender measuring opens in isolation may believe engagement is rising when in reality MPP is doing the heavy lifting. Click rate is now the more reliable engagement signal.
- The 4.3-point gain in our SES data is partly real and partly measurement artefact. The Gmail-enforcement-driven sender-quality improvement (Phase 2 above) is genuine; the MPP-driven inflation is measurement only. We cannot say what fraction of the 18.9% 2026 Q2 number reflects real recipient engagement.
The Gmail/Yahoo Bulk Sender Effect
Gmail and Yahoo introduced strict bulk sender requirements in February 2024 (Google, 2026): SPF and DKIM authentication required, one-click unsubscribe required, and complaint rates kept under 0.3%. Senders not in compliance saw their email aggressively filtered or rejected.
The effect on our aggregate SES open-rate data is visible: a sharp step up in 2024 Q4 (19.4% open rate, vs the 17.5-18.8% baseline through earlier 2024). The most plausible mechanism is sender selection. Operators who hadn't been running good list hygiene either upgraded their practices to keep sending or stopped sending entirely. The remaining cohort skewed toward higher-quality senders with more engaged audiences, which moved the aggregate metric meaningfully.
This is consistent with what we see in the bounce-rate data over the same period - the post-2024 bounce baseline is slightly lower than the pre-2024 baseline, consistent with a higher-quality sender mix.
Where the Recipients Actually Are
Recipient geography across the dataset:
| Country | Share of recipients |
|---|---|
| United States | 37.4% |
| Brazil | 18.4% |
| United Kingdom | 8.9% |
| Germany | 5.8% |
| Sweden | 4.5% |
| France | 4.0% |
| Netherlands | 3.8% |
| Norway | 3.2% |
| Spain | 3.1% |
| Belgium | 2.1% |
| Denmark | 1.8% |
| All others | 7.0% |
The geographic mix shapes the open-rate measurement. The high share of US recipients (37%) means a meaningful slice of measured opens are MPP-inflated, since iPhone penetration in the US is roughly 55%. The European recipient share (collectively about 40%) is somewhat less affected because Android use is higher across most European markets. The Brazil concentration (18%) is a relatively engaged audience for Mailblast's customer base, driven by a strong base of Brazilian SaaS and marketing operators serving the LATAM market.
We deliberately don't publish per-country open rates here because the per-country sender-mix confound is too large to disentangle from aggregate data. The question "is the US open rate higher than the European one" is really "are US-targeted senders different from European-targeted senders" and that's not a deliverability question.
What to Do With This Trend
The open-rate trend matters operationally for a few reasons:
- Don't compare your 2026 open rate to a 2022 benchmark. Industry-published benchmarks from before MPP saturated the market understate what's possible in modern measurement. A 22% open rate in 2026 isn't comparable to a 22% open rate in 2021 - the measurement baseline has shifted.
- Click rate is now the better engagement metric because it requires actual user action that MPP doesn't replicate. If you must pick a single engagement signal to track, pick click rate.
- Account for the post-2024 step up when interpreting your own numbers. A sender whose open rate increased 3-5 points in 2024 is roughly tracking the SES cohort baseline, not necessarily outperforming.
- Watch the post-2025 normalisation. The 2025 Q1 peak at 20.3% hasn't held. Subsequent quarters have settled back into the 17.6-19.0% band, suggesting the Gmail enforcement effect was a one-time compositional shift rather than ongoing improvement.
See list size vs deliverability for the data on how list size shapes open rate (small lists at 53% vs large lists at 5%).
FAQ
What is a typical open rate for Amazon SES marketing email?
Based on aggregate Mailblast campaign data, the quarterly open rate for Amazon SES marketing sends has climbed from 14.6% (2023 Q1) to 18.9% (2026 Q2). The peak was 2025 Q1 at 20.3%, likely a post-Gmail/Yahoo Feb 2024 enforcement effect. A 15-20% aggregate open rate is healthy for typical SES sending.
How has Apple Mail Privacy Protection affected open rate measurement?
Apple's Mail Privacy Protection (MPP) launched in September 2021 and has been the largest single influence on open-rate measurement since (Apple, 2026). MPP pre-fetches images, which causes Apple Mail and Apple-relayed inboxes to register opens regardless of whether the recipient actually opened the message. The effect is to inflate measured open rates for senders with significant Apple-using audiences, without representing real engagement change.
Did Gmail and Yahoo Feb 2024 enforcement change open rates?
Open rates in the data show a meaningful step up post-Feb 2024. The 2024 Q4 quarterly aggregate hit 19.4% (vs 16.7% in 2023 Q4); 2025 Q1 peaked at 20.3%. The likely explanation is selection: Gmail and Yahoo enforcement (Google, 2026) pushed problem senders out of the SES ecosystem, leaving the remaining cohort skewing toward higher-quality senders with more engaged audiences.
Which countries have the highest open rates on Amazon SES?
Recipient country composition matters less than sender behaviour, but the data shows variance. Across the largest recipient countries, US-bound campaigns (37.4% of total recipients) have similar engagement to UK-bound campaigns; Brazil-bound (18.4% of recipients) skews differently because of distinct B2C campaign patterns common in the Brazilian Amazon SES sender base. We avoid publishing per-country open rates because of the per-country sender-mix confound.
Are open rates a reliable measure of campaign performance?
Less so than they used to be. Apple MPP, image-blocking by mailbox providers, and the post-pandemic shift in email habits have all reduced open rate's correlation with actual engagement. Click rate is now a more reliable engagement signal. For Amazon SES senders specifically, the most useful metrics are click rate (engagement), bounce rate (list quality), and complaint rate (content quality) - in that order.
How Mailblast Tracks Open Rate
Mailblast operates on your own Amazon SES account (BYO-SES, customer's own AWS credentials), so the open events reported come from the standard SES open-tracking pixel routed through Mailblast's analytics pipeline. Per-campaign open rate, click rate, unsubscribe rate, and per-link click counts are visible in the campaign report alongside the recipient-level event timeline. The aggregate numbers in this post are computed from the same underlying reporting data that powers each customer's dashboard.
The trend data informs how Mailblast frames benchmarks inside the product: a 15-20% aggregate open rate is healthy in the current measurement regime; expect more volatility quarter-to-quarter than legacy benchmarks suggest; track click rate alongside opens because MPP has reduced opens' standalone signal value.
Methodology: aggregate open rates by calendar quarter across all non-suspended Mailblast Amazon SES sends from 2023-01-01 to 2026-06-10. Volume-weighted using total opens divided by total recipients. Accounts with aggregate bounce rate at or above 3% are excluded as they are in active SES reputation trouble and not representative of standard deliverability. AWS thresholds quoted from official AWS SES documentation. Apple MPP and Google sender guidelines context drawn from public Apple and Google documentation.
Disclosure: Mailblast is a hosted management layer for your own Amazon SES account. All sending in this dataset is BYO-SES; Mailblast is not a hosted ESP pooling SES centrally.