Use the Shippo API to buy a domestic shipping label with special handling (signature required, Saturday delivery) via shipment extras
domain: docs.goshippo.com · 5 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Create a Shipment via POST to /v1/shipments; include a 'extra' object at the shipment level with 'signature_confirmation' set to 'STANDARD', 'ADULT', or 'INDIRECT' and 'saturday_delivery': true for applicable services
Retrieve the rates from the response; special handling fees appear as additional charges on the rate object's 'amount' field
Select the desired rate object_id and POST to /v1/transactions with it to purchase the label
Verify the purchased label reflects the extras by inspecting the transaction's label_url; some carriers print the signature/Saturday delivery indicator directly on the label
Not all carrier/service combinations support Saturday delivery or all signature types; filter rates by checking 'carrier' and 'service_level' before offering the extra to end users
Known gotchas
Saturday delivery is only available for certain carrier services and ZIP code pairs; purchasing it for ineligible routes results in a label fee without guaranteed Saturday delivery
Adult signature required has different carrier compliance implications (IATA, alcohol, firearms regulations) than standard signature; use 'ADULT' only when legally required
Special handling extras add cost at label purchase time; present the full rate including extras to customers before purchase to avoid billing disputes
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