Here is a comparison with a twist: it ends in a three-way tie. Over the 180 days ending July 2026, the online systems of UPS, USPS, and FedEx all ran at 100% with zero major incidents. If your shipping stack has problems, the carriers' digital infrastructure is probably not where they live.
The numbers, side by side
| Metric (180 days ending July 2026) | UPS | USPS | FedEx |
|---|---|---|---|
| Uptime (major/critical incidents) | 100% | 100% | 100% |
| StatusBird reliability grade | A+ | A+ | A+ |
| Major or critical incidents | 0 | 0 | 0 |
| Total downtime | 0 minutes | 0 minutes | 0 minutes |
How these numbers are measured: StatusBird checks each service's status every 2 minutes, around the clock. Uptime counts major and critical incidents over the 180 days ending July 2026; brief degraded periods are excluded so chronically noisy status pages do not distort the comparison. Full details on the methodology page.
So why does shipping feel so unreliable?
Because the software layer on top of the carriers is the least reliable part of e-commerce infrastructure. In the same 180-day window: AfterShip, the tracking-page provider, earned a D grade with 3,548 minutes (59 hours) of major-incident downtime, the worst record among all 84 services StatusBird monitors. Shippo logged 5 major incidents. ShipStation had a single incident, but its April 2026 outage stalled label creation for most of a business day (postmortem here). The full comparison is in ShipStation vs Shippo vs ShipBob.
What about physical delivery performance?
To be precise about what this data covers: these are the carriers' online systems (tracking APIs, label systems, websites), not on-time delivery rates for physical packages. A carrier can have perfect system uptime and still deliver your package late in a snowstorm. But when your store's tracking pages break or label purchases fail, it is the systems layer, and in this window that layer failed above the carriers, not at them.
The monitoring setup for shipping stacks
Monitor your label software and your tracking provider, not just the carriers. Histories: UPS, USPS, FedEx, and the one to actually worry about, AfterShip.
Start monitoring your stack free with StatusBird: 3 services, no credit card required. Pro is $29/month for all 84 services with SMS, email, Slack, Teams, and Discord alerts within 2 minutes of a status change.