At a glance
Share of USPS shipments that received an exception scan in transit. Exception scans are non-routine events such as “delivery attempted, addressee not in”, “delivery exception, address unknown”, “delivery exception, no access to delivery point”, “carrier unable to deliver”, “weather embargo”. The exception-rate is the leading-indicator card for late deliveries: an exception scan precedes a late-or-failed delivery by 12 to 48 hours, sometimes longer for rural routes.
| What it counts | COUNT(shipments WHERE tracking events INCLUDE any exception code) / COUNT(shipments) over the trailing 30 days. Exception codes are USPS Tracking event codes outside the routine acceptance/processing/in-transit/delivered set. |
| Exception event types | (1) Delivery attempted (recipient absent, no safe drop-off location). (2) Delivery exception (insufficient address, addressee unknown, refused). (3) Forwarded (recipient moved, USPS forwarding service active). (4) Held at facility (recipient pickup required, hold mail in effect). (5) Weather embargo (route suspended for storm or natural disaster). (6) Damaged (parcel torn, contents leaking, requires repackaging). |
| Lead-indicator semantics | Each exception is a yellow flag, not a confirmed late. Many resolve on next-day-attempt and deliver on time; others escalate to delays of 1 to 7 days. The card is most useful as a 24 to 48 hour early warning for the on-time number. |
| Service level scope | All USPS services pooled. Priority Mail, Priority Mail Express, First-Class Package, Ground Advantage, Parcel Select, Media Mail. Exception rates are similar across services since they reflect address quality and customer behaviour rather than service speed. |
| Returns / RTO | Excluded. RTS shipments have their own Returned to Sender tracker. |
| Holiday/election surge | Exception rates spike during November-December and around US elections. Drivers: address-quality pressures from hand-written gift labels, recipient-not-home from holiday travel, weather embargoes from Q4 storms, suspended routes during named-storm events. Expect 1.5x to 2.5x normal exception rate in November-December. |
| Address-quality signal | A persistently high exception rate often points to upstream address-validation problems. If the merchant’s checkout doesn’t validate ZIP+4 or apartment numbers, exception rates run 2 to 3x higher than for merchants with USPS-API-validated addresses at checkout. |
| Time window | 30D vsP (rolling 30 days, period-over-period comparison) |
| Alert trigger | >3% (warn). Steady-state DTC merchants run 1 to 2.5%; above 3% signals systemic address-quality, route-coverage, or weather-surge issues. |
| Sentiment key | gauge with thresholds good=1, warn=3 (lower is better) |
| Roles | owner, operations |
Calculation
Calculated automatically from your USPS data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.Worked example
A US DTC apparel merchant shipping out of Seattle, primarily USPS Ground Advantage and Priority Mail. Reading taken at 09:00 PT on 12 Mar 26 for the trailing 30 days vs the prior 30 days.| Exception type | Shipments affected | % of total | Vs prior 30D |
|---|---|---|---|
| Delivery attempted (recipient not in) | 285 | 1.8% | +0.3 ppt |
| Delivery exception (address) | 168 | 1.1% | +0.6 ppt |
| Forwarded | 62 | 0.4% | flat |
| Held at facility | 41 | 0.3% | flat |
| Weather embargo | 38 | 0.2% | -0.1 ppt |
| Damaged | 12 | 0.1% | flat |
| All exceptions (this card) | 606 | 3.9% | +0.8 ppt vs 3.1% |
- The +0.6 ppt rise in “Delivery exception (address)” is the headline. Investigation: the merchant added a new product page in late February that auto-fills shipping address from a third-party widget. The widget is dropping apartment numbers on roughly 8% of orders. Fix: switch to a USPS-API-validating address widget, or add a post-checkout validation step. Expected drop: 0.4 to 0.6 ppt within 2 weeks.
- “Delivery attempted” at 1.8% is normal but climbing. Recipient-not-home is irreducible to about 1.5%; the +0.3 ppt suggests holiday-season vacationers (typical for Spring Break). Will normalise within 2 weeks.
- Each exception is a 1-to-3-day on-time risk. The 606 exceptions in the period generated roughly 280 to 380 late deliveries downstream. The exception rate today is the on-time rate slip in 24 to 72 hours.
- Weather embargo at 0.2% is low for the season. Pacific Northwest had a mild February. Compare against December readings (typically 0.8 to 1.5%) for context.
- Damaged at 0.1% is operational. 12 damaged parcels per 30 days is normal at this volume; if it climbs above 0.3%, investigate packing process or carrier handling. The damaged-parcel rate also feeds Open Claims for parcels declaring contents over $50.
Sibling cards merchants should reference together
| Card | Why pair it with Exception Rate | What the combination tells you |
|---|---|---|
| On-Time Delivery Rate | Lagging confirmation. | Exception rate climbing 24 to 72 hours before on-time-rate drops is the early-warning signal. Act on the exception, not the on-time number. |
| Late Shipments | Lagging count. | Roughly 50 to 65% of exceptions become late deliveries; the rest resolve on next attempt. |
| Returned to Sender | Worst-case outcome. | Address exceptions that fail correction roll forward into RTS within 5 to 15 days. |
| Failed Delivery Count | Severe-end of the exception spectrum. | Failed delivery is a confirmed-cannot-deliver disposition; exception is the upstream signal. |
Cross-connector: shopify.refund_rate | Customer-impact lag. | Address-exception rate predicts a refund-rate climb at 10 to 20 day lag (the exception, then the failed delivery, then the customer dispute). |
| Cross-connector: address-validation tool data (USPS Web Tools, Google Address Validation) | Upstream root cause. | High address-exception rate often indicates checkout-side address validation isn’t firing. |
Reconciling against the vendor’s own dashboard
Where to look in USPS’s own dashboard: USPS does not surface an aggregate exception-rate report in PostalOne! by default. Per-shipment exception scans are visible at USPS Tracking for each tracking number; aggregate views require either PostalOne! reports filtered to non-routine event codes, or third-party tracking aggregators (AfterShip, ShipBob, EasyPost). The card is the primary aggregate view for most shippers. Why our number may legitimately differ from the vendor’s:| Reason | Direction | Why |
|---|---|---|
| Event-code scope | Either | The card includes any non-routine scan (delivery attempted, exception, forwarded, held, weather, damaged). USPS’s portal sometimes excludes “delivery attempted” from exception reports because it is so common. |
| Tracking-data quality | Card may show lower | USPS sometimes posts partial scans that don’t reach the Tracking API. Rural routes have the worst scan-event coverage. |
| Time zone | <1 day off | UTC vs local-time boundary. |
| Card | Expected relationship | What causes legitimate divergence |
|---|---|---|
fedex.fed_exception_rate | Peer carrier. | Different parcel-weight distribution and customer-mix; FedEx tends to run lower exception rates because of better address-validation at booking. |
easypost.eas_exception_rate | Aggregator view. | EasyPost includes USPS exceptions plus all other carriers; filter to USPS for like-for-like. |