> ## Documentation Index > Fetch the complete documentation index at: https://docs.vortexiq.ai/llms.txt > Use this file to discover all available pages before exploring further. # Sub-Carrier OTD Comparison, ShipTheory > Side-by-side OTD comparison across ShipTheory's sub-carriers - feeds the carrier-renegotiation conversation. Key Metrics. How to read it, why it matters, and how ... **Metrics type:** [Key Metrics](/nerve-centre/overview#metrics-types-explained) • **Category:** [Shipping & Courier](/nerve-centre/connectors#connectors-by-type) > Side-by-side OTD comparison across ShipTheory's sub-carriers - feeds the carrier-renegotiation conversation. Key Metrics. ## At a glance > Side-by-side On-Time Delivery rate **per underlying UK sub-carrier** (Royal Mail, DPD, Evri, Parcelforce, Yodel). The card that justifies why ShipTheory exists: by exposing each sub-carrier's reliability directly, it lets the operator tune the rate-shop ruleset and feeds carrier-renegotiation conversations with empirical data. 30D window with a per-carrier `<90%` alert. | | | | ------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **What it counts** | `COUNT(shipments WHERE actual_delivery_date <= expected_delivery_date) / COUNT(delivered shipments)` for each `sub_carrier` over a 30-day window. | | **API endpoint** | `GET /shipments` joined with carrier tracking webhook for `delivered_at`, grouped by `sub_carrier`. | | **Delivery success criterion** | Carrier POD `delivered_at <= expected_delivery_date`, normalised across the different UK carrier POD models (Royal Mail signature/scan, DPD photo+signature, Evri photo). | | **On-time threshold** | Carrier-promised `expected_delivery_date` per shipment, no grace. Each sub-carrier's promise is its own; like-for-like across services within sub-carrier, not across sub-carriers. | | **Returns / RTO** | Outbound only. | | **Service level scope** | Within each sub-carrier, all services pooled. So "Royal Mail" combines Tracked 24, Tracked 48, Special Delivery; "DPD" combines Next Day, Two Day; etc. | | **The point of the card** | ShipTheory's whole reason for being is the rate-shop dynamic across UK carriers. This card is the **direct evidence** for tuning that rate-shop. The aggregate OTD card hides which sub-carrier is dragging; this card surfaces it. | | **Renegotiation use** | Quarterly business reviews with sub-carriers cite this card. A sub-carrier running materially below peer median for 90 days is a renegotiation lever (volume threat, contract revisions, service-tier escalations). | | **Currency** | Not applicable. | | **Time window** | `30D` (rolling 30-day window per sub-carrier) | | **Alert trigger** | `any sub-carrier <90%`. The card alerts as soon as any individual sub-carrier falls below 90% OTD even if aggregate is healthy. | | **Sentiment key** | `on_time_delivery_rate` | | **Roles** | owner, operations | ## Calculation Calculated automatically from your ShipTheory data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading. ## Worked example The UK home & garden merchant. Reading taken at 09:00 GMT on 12 Mar 26 for the trailing 30 days. | Sub-carrier | Shipments | Delivered on time | OTD rate | Alert | | -------------------- | ---------- | ----------------- | --------- | ----------------- | | Royal Mail | 6,500 | 6,175 | 95.0% | OK | | DPD | 2,820 | 2,792 | 99.0% | OK | | Evri | 2,960 | 2,575 | 87.0% | **\<90%, FIRING** | | Parcelforce | 1,120 | 1,075 | 96.0% | OK | | Yodel | 380 | 327 | 86.1% | **\<90%, FIRING** | | **All sub-carriers** | **13,780** | **12,944** | **93.9%** | (aggregate OK) | The aggregate reads **93.9%** OTD, comfortably above 90%. The sub-carrier cut surfaces that **both Evri at 87% and Yodel at 86.1%** are below threshold. Five things to notice: 1. **Aggregate hides two sub-carrier-level problems.** Evri at 87% on 21% of volume + Yodel at 86.1% on 3% of volume both being absorbed by Royal Mail (95%) and DPD (99%) on bigger shares. Without this card, the operator sees "shipping is fine". 2. **DPD at 99% is the renegotiation benchmark.** Their structural reliability is the comparator; if any other sub-carrier sits 5+ points below DPD on 30D, the rate-shop can rationally shift volume away. The card is the empirical evidence. 3. **Evri's 87% is the operative intervention.** Most ShipTheory operators respond by tightening the rate-shop ruleset to push Evri-eligible parcels (low-value, non-urgent) to Royal Mail Tracked 48 instead. The cost lift is GBP 0.30 to 0.60 per parcel; the OTD recovery is 5 to 8 percentage points. 4. **Yodel at 86.1% on 380 shipments is structurally fragile.** Many ShipTheory accounts exclude Yodel entirely from rate-shop after seeing this card consistently fire on Yodel for 60+ days. The cost saving (Yodel typically GBP 0.20 to 0.40 cheaper than Royal Mail equivalents) does not justify the OTD risk for most mid-market merchants. 5. **The card is the QBR slide.** Quarterly business reviews with each sub-carrier should reference 90-day rolling OTD from this card. Royal Mail at 95% on 47% volume share is the loyalty case; Evri at 87% is the renegotiation case; DPD at 99% is the gold-standard reference. ## Sibling cards merchants should reference together Sub-carrier OTD comparison answers "which carrier is dragging?" Pair with these to act. | Card | Why pair it with Sub-Carrier OTD Comparison | What the combination tells you | | --------------------------------------------------------------------------------------------- | ------------------------------------------- | ------------------------------------------------------------------------------------------------------- | | [On-Time Delivery Rate](/nerve-centre/kpi-cards/ship-theory/on-time-delivery-rate) | The aggregate counterpart. | Aggregate green + a sub-carrier red = the cross-cut is the only place the issue is visible. | | [Sub-Carrier Volume Mix](/nerve-centre/kpi-cards/ship-theory/sub-carrier-volume-mix) | Volume share per sub-carrier. | A sub-carrier with low OTD and low share is low-risk; low OTD and high share is operational priority. | | [Late Shipments](/nerve-centre/kpi-cards/ship-theory/late-shipments) | The count counterpart. | This card answers "where is the OTD coming from"; the late count card answers "how much is it costing". | | [Avg Shipping Cost](/nerve-centre/kpi-cards/ship-theory/avg-shipping-cost) | Cost-vs-reliability trade-off. | Together: the rate-shop tuning conversation. | | [Sub-Carrier OTD by Service](/nerve-centre/kpi-cards/ship-theory/otd-by-route) | One layer deeper, by route. | If Evri is dragging, is it Evri Standard or Evri Next Day? | | Cross-connector: [`shopify.refund_rate`](/nerve-centre/kpi-cards/shopify/refund-rate) | Downstream impact. | Sub-carrier OTD drop predicts Shopify refund-rate climb at 7 to 14 days lag. | | Cross-connector: [`bigcommerce.refund_rate`](/nerve-centre/kpi-cards/bigcommerce/refund-rate) | Same as Shopify for BC merchants. | Same lag. | | Cross-connector: customer NPS surveys | Downstream sentiment. | Sustained OTD drop on a high-share carrier predicts NPS softening over 14 to 30 days. | ## Reconciling against the vendor's own dashboard **Where to look in ShipTheory's own dashboard:** [ShipTheory Dashboard](https://app.shiptheory.com/) → **Reports → Carrier Performance**. The portal exposes the same per-sub-carrier OTD with bar comparison, plus drill-down into per-service breakdown. Closest like-for-like view: *Last 30 Days, Group By: Carrier*. **Why our number may legitimately differ from ShipTheory's portal:** | Reason | Direction | Why | | -------------------------- | ---------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | **Service-level grouping** | Either | The card pools all services within a sub-carrier; the portal sometimes splits Royal Mail Tracked 24 from Tracked 48. Toggle the portal to "all services within carrier" for like-for-like. | | **Tracking sync lag** | Ours lower for "today" | Royal Mail and Evri tracking webhooks lag 4 to 12 hours during peak; T-2 days fully reconcile. | | **Promise-date staleness** | Ours stricter | Card holds carriers to original promise; portal sometimes recalculates after carrier embargo. | | **In-transit exclusion** | Both exclude | Parcels still in transit are out of both numerator and denominator. | | **Timezone** | Boundary days off | Card UTC; portal GMT/BST. | **Cross-connector reconciliation:** | Card | Expected relationship | What causes legitimate divergence | | ---------------------------------------------------------------------- | ----------------------------------------------------------- | ----------------------------------------------------------------------- | | Direct sub-carrier dashboards (Royal Mail OBA, DPD insight, Evri Send) | Peer measurement of same shipments from carrier side. | Carriers track to internal SLA tables, not your stored promise. | | [`shopify.refund_rate`](/nerve-centre/kpi-cards/shopify/refund-rate) | Downstream sentiment for the affected sub-carrier's volume. | Refund-rate is order-level, not sub-carrier-level; correlation is soft. | ***
Documentation cross-reference (for agencies running multi-platform stacks) Per-sub-carrier OTD comparison is unique to multi-carrier orchestrators. Single-carrier platforms cannot produce this view. * [ShippyPro OTD by Sales Channel](/nerve-centre/kpi-cards/shippy-pro/shippypro-otd-by-sales-channel) (the equivalent EU cut, but by sales channel rather than sub-carrier) * ShipStation per-carrier reliability (peer aggregator, similar slice)
## Known limitations / merchant FAQs **Why is Evri so consistently below 90%?** Structural. Evri's distributed self-employed-courier model produces variability that the contracted-courier networks (DPD, Royal Mail) do not have. Most ShipTheory accounts running Evri-heavy mix accept this and tier Evri to lowest-value parcels. **My DPD share is small (8%). Should I shift more to DPD?** Depends on the cost-vs-OTD trade. DPD averages \~30 to 50 percent more per parcel than Evri on equivalent service tier. Shifting volume to DPD lifts OTD but compresses margin. The decision is per-SKU; high-margin items absorb the cost, low-margin do not. **How do I use this for sub-carrier renegotiation?** Three steps. (1) Pull 90-day rolling OTD from this card per sub-carrier; export to CSV. (2) Pair with monthly volume share and avg cost per sub-carrier. (3) Present in the QBR: "we sent X parcels through you, OTD was Y, peer median is Z, here is the volume threat if Y does not improve". Carriers respond to evidence, not feelings. **Royal Mail strikes, how does the card behave?** Royal Mail OTD drops sharply during strike weeks (down 20 to 30 points), then recovers over 4 to 8 weeks. The 30-day window means the strike impact lingers in the card's reading for \~6 weeks after strike ends. Use the trend view, not the snapshot, during/after strikes. **What about service-level filtering, does the card mix Tracked 24 with Tracked 48?** Yes, all services within a sub-carrier are pooled. Tracked 24 typically runs 95%+ OTD; Tracked 48 runs 92 to 95%. If your Royal Mail mix shifts to Tracked 48, the card shows Royal Mail "dropping" even though both services are healthy individually. Use [Sub-Carrier OTD by Service](/nerve-centre/kpi-cards/ship-theory/otd-by-route) for the deeper cut. **Yodel, should I just turn it off?** Common decision at mid-market scale. The cost saving on Yodel is small in absolute terms (GBP 0.20 to 0.40 per parcel cheaper than Royal Mail Tracked 48 equivalents); the OTD risk and customer-complaint volume often does not justify. Most operators tier Yodel to truly low-value, non-urgent parcels only. **Christmas peak, all sub-carriers degrade together?** Roughly proportionally. All UK carriers run hot through November and December; Evri and Yodel typically the worst (down 10 to 15 points), Royal Mail and DPD hold better (down 4 to 7 points). The relative ordering stays similar but the gap widens. Plan rate-shop adjustments and customer comms for peak. **B2B / wholesale, different patterns?** Yes. B2B typically uses DPD priority or Parcelforce Express; OTD on B2B-only volume runs 98%+ structurally. The card pools B2B with retail; if B2B mix is material, segment via the per-source cut in the export. **What is the "carrier-renegotiation conversation" in the headline?** The strategic outcome of using this card. Multi-carrier merchants rotate their carrier mix based on data; this card is the canonical evidence input. The renegotiation conversation either lifts the underperforming carrier's service or shifts their volume share down. **Cross-border (UK to EU), does that affect this card?** Yes, but it is invisible if you do not segment. EU export shipments via ShipTheory typically use DPD or Parcelforce; their OTD on EU lanes runs lower than UK domestic (5 to 10 points). If your EU volume is rising, the card may show DPD or Parcelforce OTD slipping; segment the data to confirm. *** ### Tracked live in Vortex IQ Nerve Centre *Sub-Carrier OTD Comparison* is one of hundreds of KPI pulses Vortex IQ tracks across ShipTheory and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English. [Start for free](https://app.vortexiq.ai/login) or [book a demo](https://www.vortexiq.ai/contact-us) to see this metric running on your own data.