Inferensys

Glossary

First Attempt Delivery Rate (FADR)

A key performance indicator measuring the percentage of parcels successfully delivered on the first visit, directly impacting cost and customer satisfaction.
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LAST-MILE KPI

What is First Attempt Delivery Rate (FADR)?

First Attempt Delivery Rate is the critical logistics metric that measures the percentage of parcels successfully delivered to the end customer on the initial visit, without requiring re-delivery attempts.

First Attempt Delivery Rate (FADR) is a key performance indicator calculating the ratio of successful first-time deliveries to total outbound deliveries within a given period. A failed first attempt, triggered by a Proof of Delivery (PoD) exception such as a missed Service Level Agreement (SLA) Adherence window or a recipient absence, directly generates costly reverse logistics and re-delivery workflows.

Optimizing FADR relies on the precision of upstream systems, including ETA Prediction Engines and Geocoding accuracy, to ensure drivers arrive within the promised Geofencing window. A high FADR is the primary driver of reduced cost-per-delivery and elevated customer satisfaction, making it the definitive measure of last-mile operational efficiency.

DEFINITIONAL ATTRIBUTES

Key Characteristics of FADR

First Attempt Delivery Rate (FADR) is a critical last-mile logistics metric that quantifies the percentage of parcels successfully delivered on the initial visit. The following characteristics define its operational and financial significance.

01

Core Calculation Formula

FADR is calculated by dividing the total number of parcels successfully delivered on the first attempt by the total number of parcels out for delivery, expressed as a percentage.

  • Formula: (First Attempt Deliveries / Total Outbound Parcels) × 100
  • Inverse Metric: The complement of FADR is the First Attempt Failure Rate, which directly triggers exception management workflows.
  • Granularity: It is typically measured daily but is most actionable when aggregated by driver, route, or delivery window.
02

Direct Cost Driver

A failed first attempt generates a significant non-linear cost increase, often making the last mile the most expensive leg of the supply chain.

  • Re-attempt Costs: Each subsequent delivery attempt can cost 2-3x the original drop due to additional fuel, labor, and vehicle depreciation.
  • Reverse Logistics: Failures often trigger costly returns processing and restocking fees.
  • Customer Service Load: Failed deliveries spike call center volume with WISMO (Where Is My Order?) inquiries, increasing operational overhead.
03

Customer Satisfaction Proxy

FADR serves as a direct leading indicator for Net Promoter Score (NPS) and customer retention in e-commerce.

  • Convenience Failure: A missed delivery represents a broken brand promise, often resulting in immediate churn.
  • Delivery Anxiety: Low FADR rates condition customers to expect failure, reducing their willingness to choose premium shipping options.
  • Retail Benchmark: Top-quartile logistics providers maintain FADR rates above 95%, while sub-90% performance is typically correlated with negative customer sentiment.
04

Root Causes of Failure

Diagnosing low FADR requires segmenting failures into distinct, addressable categories rather than treating them as a monolithic problem.

  • Recipient Not Available (RNA): The most common cause, often mitigated by dynamic time window optimization and proactive SMS/email notifications.
  • Address Quality Issues: Incorrect or poorly standardized addresses cause geocoding failures, sending drivers to wrong locations.
  • Access Restrictions: Gated communities, secure office buildings, or missing entry codes without pre-communicated instructions.
  • Driver Behavior: Premature stop-closure or failure to wait sufficient time at the delivery point.
05

Predictive Intervention Levers

Modern logistics platforms use machine learning to predict failure probability before a vehicle departs, enabling preemptive action.

  • ETA Prediction Engines: Gradient boosted trees analyze historical patterns to predict precise arrival times, enabling narrow, accurate delivery windows.
  • Dynamic Re-Routing: Real-time traffic and weather data adjust routes to maintain promised windows.
  • Recipient Engagement: Automated systems trigger personalized delivery confirmations and live tracking links to ensure recipient availability.
  • Address Standardization: AI-powered parsing and validation against postal authority databases correct errors before label generation.
06

Relationship to OTIF

FADR is a necessary but insufficient condition for achieving high On-Time In-Full (OTIF) scores, a critical retail compliance metric.

  • Temporal Component: A parcel can be delivered on the first attempt but still fail OTIF if it arrives outside the specified time window.
  • Integrity Component: FADR does not measure whether the correct items were delivered in the correct quantity.
  • Hierarchical Metric: FADR is a subset of the broader delivery success framework; optimizing for FADR alone without considering OTIF can lead to rushed, inaccurate deliveries.
FIRST ATTEMPT DELIVERY RATE

Frequently Asked Questions

Explore the critical questions surrounding First Attempt Delivery Rate (FADR), the key performance indicator that directly impacts last-mile logistics costs, customer satisfaction, and operational efficiency.

First Attempt Delivery Rate (FADR) is a key performance indicator (KPI) that measures the percentage of parcels successfully delivered to the end customer on the initial delivery visit, without requiring any subsequent attempts. It is calculated by dividing the total number of parcels delivered on the first attempt by the total number of parcels out for delivery, then multiplying by 100. A high FADR indicates an efficient last-mile operation, directly minimizing the costly overhead associated with re-delivery, returns processing, and customer service inquiries. This metric is a direct reflection of the accuracy of underlying systems, including geocoding, address standardization, and ETA prediction engines.

Prasad Kumkar

About the author

Prasad Kumkar

CEO & MD, Inference Systems

Prasad Kumkar is the CEO & MD of Inference Systems and writes about AI systems architecture, LLM infrastructure, model serving, evaluation, and production deployment. Over 5+ years, he has worked across computer vision models, L5 autonomous vehicle systems, and LLM research, with a focus on taking complex AI ideas into real-world engineering systems.

His work and writing cover AI systems, large language models, AI agents, multimodal systems, autonomous systems, inference optimization, RAG, evaluation, and production AI engineering.