Aggregate open rates on Amazon SES marketing campaigns climbed from 15.76 percent in 2023 to 18.94 percent in 2026, while aggregate bounce held at 0.10 percent and complaint at 0.007 percent - fifty and fourteen times below the AWS warning thresholds of 5 percent and 0.1 percent respectively (AWS, 2026). Those numbers are based on aggregate Mailblast campaign data spanning January 2023 through December 2026. We share four years of bounce, open, click, complaint, and unsubscribe metrics, broken out by year, quarter, AWS region, recipient country, and send volume tier.
Methodology
The dataset is every campaign sent through Mailblast where the AWS reporting summary was populated and the sending account met three quality conditions. Accounts must be non-suspended in the Mailblast platform. Accounts must have an aggregate four-year bounce rate below 3 percent - this excludes senders already in active SES reputation trouble whose numbers would distort cohort statistics. Campaigns must have a completed AWS reporting summary (populated after a campaign completes and feedback events arrive).
After filters, the dataset spans a large cohort of active Mailblast accounts across four years. Reporting coverage before 2023 is sparse (3-17 percent of campaigns), which is why the window starts at 2023-01-01.
Three caveats. First, every account in this dataset operates on its own AWS SES account - Mailblast is a hosted management layer on top of customer-owned SES, not a centrally-hosted ESP. The numbers describe SES behaviour for senders who chose this architecture. Second, AWS does not expose inbox-vs-spam-folder placement; engagement and complaint rates are deliverability proxies, not direct placement signals. Third, ISP-level breakdowns (Gmail vs Yahoo vs Outlook) are not available without per-recipient queries; this analysis is at the recipient-country and campaign-aggregate level only.
The four-year annual roll-up
Across the four full and partial years in the dataset, aggregate engagement metrics improved steadily while error metrics held within a narrow band well under AWS thresholds. The aggregate bounce rate ran between 0.096 percent and 0.118 percent - roughly fifty times below the 5 percent AWS warning threshold (AWS, 2026). The aggregate complaint rate held below 0.009 percent in every year, fourteen times below the 0.1 percent threshold.
| Year | Bounce % | Complaint % | Open % | Click % | Unsub % |
|---|---|---|---|---|---|
| 2023 | 0.100 | 0.0070 | 15.76 | 0.42 | 0.080 |
| 2024 | 0.096 | 0.0088 | 18.37 | 0.56 | 0.086 |
| 2025 | 0.118 | 0.0072 | 18.80 | 0.57 | 0.084 |
| 2026 (YTD Dec 10) | 0.104 | 0.0053 | 18.94 | 0.70 | 0.079 |
The open rate trend is the clearest movement: from 15.76 percent in 2023 to 18.94 percent year-to-date in 2026, a 3.18-point absolute lift. That tracks the industry pattern post-Gmail-Yahoo Feb 2024 bulk-sender enforcement, when authenticated senders increasingly clustered above the 15-20 percent open rate band as poorly-authenticated competitors got greylisted (Validity, 2026). Bounce rate remained noisy but stable; the slight 2025 uptick reflects a smaller campaign mix dominated by newer accounts still settling in.
Quarterly trend: where the curve actually moved
Quarterly aggregation reveals two patterns the annual roll-up smooths over. Open rates stepped up sharply in 2024-Q1 - exactly when the Gmail and Yahoo bulk-sender requirements took effect - and have held in the 18-21 percent band ever since. Complaint rates peaked in 2024-Q3 at 0.010 percent before settling back into the 0.005-0.008 percent range. Click rates have crept upward across the full window, from 0.32 percent in 2023-Q2 to 0.80 percent in 2026-Q2.
The Gmail-Yahoo enforcement marker (Feb 2024) is the visible inflection. Quarter-over-quarter the open rate stepped from 16.66 percent (2023-Q4) to 18.75 percent (2024-Q1) - a 2-point lift that has held. Senders who passed Gmail and Yahoo's tightened SPF, DKIM, DMARC, and List-Unsubscribe requirements found their authenticated mail landing more reliably.
Send volume distribution: where the emails actually go
Send-volume distribution is sharply bimodal. Smaller campaigns under 100,000 recipients account for 90 percent of campaign count but only 7 percent of total volume; campaigns in the 10,000-100,000 tier carry 61 percent of total volume; campaigns in the 100,000-1,000,000 tier carry another 38 percent.
| Send volume tier | % of volume | Bounce % | Complaint % | Open % |
|---|---|---|---|---|
| Less than 1,000 | 0.06% | 0.872 | 0.0149 | 50.62 |
| 1,000 - 10,000 | 0.7% | 0.627 | 0.0100 | 30.57 |
| 10,000 - 100,000 | 60.8% | 0.104 | 0.0076 | 18.76 |
| 100,000 - 1,000,000 | 38.4% | 0.087 | 0.0078 | 15.30 |
The pattern is consistent with what AWS sees across the platform: high-volume senders run tighter list hygiene because the consequences of an unclean list are immediate and painful (AWS, 2026). Small senders (under 1K) see 0.87 percent bounce - eight times the aggregate - because list hygiene is less consequential at that scale. The inverse pattern shows up on the open side: small sends average 50 percent open rate because senders at that scale typically email highly-engaged segments rather than full lists.
AWS region distribution: where the senders actually live
Among the accounts in the cohort, region choice was concentrated in four regions. eu-west-1 (Ireland) carries 65 percent of total volume despite a much smaller share of accounts. us-west-2 (Oregon) carries 24 percent. us-east-1 (N. Virginia) carries 9 percent, and ap-south-1 (Mumbai) carries 2 percent.
The eu-west-1 concentration is striking. Ireland-region SES accounts in this cohort carry 8x the per-account volume of N. Virginia accounts. This likely reflects two factors: GDPR-conscious senders preferring EU-region SES, and a handful of high-volume operators who chose eu-west-1 for proximity to their EU recipient base. Region choice in this dataset tracks customer infrastructure decisions, not deliverability optimisation - all four AWS regions show statistically equivalent bounce and complaint behaviour.
Recipient countries: where the emails actually land
The geo-distribution data, aggregated across all campaigns with populated geo data, is heavily concentrated in North America, Western Europe, and Brazil. The US tops the list at 37.0 percent of identified recipients, Brazil follows at 18.3 percent, the UK at 8.8 percent, and Germany at 5.7 percent. The top 10 countries account for 84 percent of all identified destinations.
| Rank | Country | Share |
|---|---|---|
| 1 | United States | 37.0% |
| 2 | Brazil | 18.3% |
| 3 | United Kingdom | 8.8% |
| 4 | Germany | 5.7% |
| 5 | Sweden | 4.5% |
| 6 | France | 4.0% |
| 7 | Netherlands | 3.8% |
| 8 | Norway | 3.1% |
| 9 | Spain | 3.1% |
| 10 | Belgium | 2.0% |
| 11-20 | DK, CH, CA, AT, PL, IT, FI, PT, IE, IN | 6.3% |
Two patterns worth flagging. Nordic countries (Sweden, Norway, Denmark, Finland) collectively account for 9.5 percent of recipients - high relative to population, consistent with the historical strength of B2B SaaS and e-commerce email programs in that region. Brazil's number-two ranking reflects a long Mailblast tail of Portuguese-speaking SaaS operators whose lists run heavily Brazilian.
What the bounce data actually says about SES
Across the full cohort, the aggregate bounce rate held at 0.10 percent - one-fiftieth of the AWS warning threshold of 5 percent and one-hundredth of the suspension threshold of 10 percent (AWS, 2026). At the campaign level, the median bounce rate sat at 0.03 percent, meaning a typical campaign in the cohort bounces 30 of every 100,000 sends. The 75th-percentile campaign bounces at 0.06 percent.
The headline implication is that SES, operated by senders who pay attention to list hygiene, produces bounce numbers that would be considered exceptional anywhere in the email industry. Mailchimp's published benchmarks across consumer ESPs range from 0.4 to 0.8 percent bounce rates depending on industry vertical (Mailchimp, 2026); the cohort here runs at one-fifth of that. The difference is partly structural - senders who chose to operate raw SES tend to be technically engaged - and partly methodological: this cohort excluded the small number of accounts that ran above 3 percent bounce, because including them would distort the read on what disciplined SES sending looks like.
See our Amazon SES bounce rate benchmarks post for the full distribution analysis by year and volume tier.
What the complaint data actually says
Complaint rate held at 0.007 percent aggregate - one fourteenth of the AWS warning threshold of 0.1 percent. Translated: roughly seven of every 100,000 sends produce a recipient pressing the "report spam" button in their email client. The 2024 peak (0.0088 percent) coincided with the post-Feb-2024 Gmail-Yahoo enforcement period when complaint feedback loops tightened across mailbox providers; by 2026 the cohort had returned to a 0.0053 percent rate.
The Gmail bulk-sender rules require complaint rates under 0.3 percent in Postmaster Tools (Google, 2024). At 0.005-0.009 percent, the cohort runs more than thirty times below that requirement. This is what disciplined opt-in marketing looks like, viewed at the platform level rather than from a single sender's vantage.
How engagement actually moved through the four years
Open rate climbed 3.18 percentage points from 2023 to 2026 - 15.76 percent to 18.94 percent in aggregate, with the median campaign open rate rising even more sharply from 16.94 percent to 23.25 percent. Click rate climbed 67 percent in relative terms, from 0.42 percent to 0.70 percent. Unsubscribe rate held remarkably stable around 0.080-0.086 percent across the entire window.
Stable unsubscribe rates against rising open rates is the clean signal here. If engagement gains were driven by list churn - cutting deadweight to inflate open rates - unsubscribe rates would have spiked. They did not. The cohort got more engagement per send without losing more subscribers per send. The most plausible explanation is the post-Feb-2024 authentication regime: authenticated mail lands more reliably, gets opened more, and produces more clicks without producing more spam complaints or list flight.
For the open-rate story in more detail by quarter and ISP, see our Amazon SES open rate trends post.
What the data does not tell us
Three honest gaps in this report. First, inbox-vs-spam-folder placement is not exposed in any AWS data source available to us. The open rate and complaint rate together imply strong inbox placement, but the proxy is indirect. Second, ISP-level breakdowns (Gmail vs Yahoo vs Outlook bounce or complaint rates) require per-recipient queries that this dataset does not include - we stayed at the campaign-aggregate level for k-anonymity reasons.
Third, this cohort excludes the small number of accounts that ran above the 3 percent bounce threshold, together accounting for well under 1 percent of analysed volume. If you include them, aggregate bounce rates climb materially - a reminder that platform-wide averages are sensitive to where you draw the line on "representative." We exclude them because their numbers reflect accounts already in active SES reputation trouble; including them would describe a population AWS is already in the process of restricting.
What it means for new SES senders
Three takeaways for anyone starting on SES in 2027.
Treat under-2-percent bounce as the operating ceiling, not 5 percent. AWS warns at 5 percent and threatens suspension at 10 percent (AWS, 2026), but disciplined senders in this cohort run at 0.1 percent. A new account hitting 2 percent is already an order of magnitude worse than the achievable baseline. That gap is the room to fix list hygiene before AWS notices.
Treat under-0.05-percent complaint as the operating ceiling, not 0.1 percent. AWS warns at 0.1 percent. The cohort runs at 0.007 percent. If your account complaint rate climbs above 0.05 percent, list-source quality is already deteriorating - it will deteriorate further before it stabilises.
Authenticate fully, then measure twice. The 2024-Q1 inflection in open rate did not happen by accident. SPF, DKIM, DMARC alignment, RFC 8058 one-click List-Unsubscribe, ARC headers if you forward - all of these moved authenticated senders into a different inbox-placement band than unauthenticated ones (Google, 2024). The 3-point open rate lift across the cohort is what authentication actually delivers when measured at scale.
How Mailblast fits into this picture
Mailblast is a hosted management layer that sits on top of the customer's own Amazon SES account. It does not centralise sending, does not pool reputation, and does not insert itself into the SMTP path beyond the API calls that hand campaigns to SES. The numbers in this report describe SES behaviour as operated by senders who chose this architecture - the customer's AWS account is doing the sending, Mailblast is doing the list management, BeeFree-based template editor, automation, suppression, and reporting layer that makes the SES API operationally usable.
For most senders evaluating where to start, the practical implication is: SES costs $0.10 per 1,000 sends; Mailblast's free plan includes analytics but not automation, and paid plans start at $10 per month (1,000 contacts) and add automation; the all-in cost at 100,000 emails per month (10,000 contacts, $20/month on the ladder) is approximately $30 per month, including the SES sending fee. The numbers in this report describe what is achievable in deliverability terms at that price point.
FAQ
What is a healthy bounce rate on Amazon SES?
Based on aggregate Mailblast campaign data, the aggregate bounce rate was 0.10 percent - fifty times below the AWS 5 percent warning threshold (AWS, 2026). At the campaign level, the median bounce rate sat at 0.03 percent. A new SES account should target staying under 2 percent through the warm-up phase and under 0.5 percent at steady state.
What is a normal complaint rate for Amazon SES?
The aggregate complaint rate across the dataset was 0.007 percent - fourteen times below the AWS 0.1 percent threshold (AWS, 2026). Senders consistently above 0.05 percent should investigate list hygiene before AWS does. Verified opt-in lists with a clear unsubscribe path typically hold complaint rates under 0.01 percent.
What open rate should I expect on Amazon SES marketing campaigns?
Aggregate open rates across the four-year window climbed from 15.76 percent in 2023 to 18.94 percent in 2026, with the median campaign open rate higher still at 23-27 percent. The aggregate is volume-weighted, so large blasts pull it down; the median better reflects what a small-to-mid-list sender sees on a typical campaign.
Which AWS region do most SES senders use?
Across the analysed accounts, eu-west-1 carried 65 percent of total volume despite a much smaller share of accounts - heavy senders cluster in Ireland. us-west-2 carried 24 percent, us-east-1 carried 9 percent, and ap-south-1 carried 2 percent. Region choice typically reflects where the customer's existing AWS footprint sits, not deliverability optimisation.
Where do Amazon SES recipients actually live?
Among the 90+ countries represented in recipient geolocation data, the US received 37 percent of identified recipients, Brazil 18 percent, the UK 9 percent, Germany 6 percent, and Sweden 4 percent. The top 10 countries account for 84 percent of all destinations. Most volume is concentrated in North America, Western Europe, and Brazil.
Disclosure: This report was produced by Mailblast, a hosted management layer for customer-owned Amazon SES accounts. The dataset is anonymised aggregate behaviour across our cohort - no customer identifiers, domain names, or campaign-level identifiers appear in the analysis. Mailblast is not affiliated with Amazon Web Services. Methodology details and exclusion rules are described in the Methodology section above.