Cost of Rework in Software Development 2026

Updated 17 April 2026

20-40%

Of engineering effort is rework

NIST 2002

85%

Typical Defect Removal Efficiency

Capers Jones 2008

$59.5B

Annual US cost of inadequate testing

NIST Planning Report 02-3

NIST Planning Report 02-3 (2002) found that 20-40% of development effort in typical US software organisations is consumed by finding and fixing defects. On a 20-person team at $200,000 fully-loaded annual cost, that is $800,000-$1,600,000 per year in rework -- a number most engineering leaders have never calculated for their own organisation.

This page presents the software-specific data from the canonical studies. For the full study descriptions, methodology notes, and caveats, see the canonical studies page. For the calculator, see the homepage.

The IBM 1-10-100 Rule Applied to Software

Barry Boehm (1981) and IBM Systems Sciences Institute (1995) established that defect fix cost increases approximately one order of magnitude per lifecycle phase. The table below shows the multipliers and their modern CI/CD-adjusted interpretation.

Detection PhaseRelative CostModern CI/CD Adjustment
Requirements / Design$1Still cheapest. CI/CD does not reduce requirements rework.
Unit / Integration Testing$5-10Fast CI catches defects within hours. Lower than 1981 data for mature teams.
System / E2E Testing$10-30Automated E2E in CI reduces this for teams with good coverage.
UAT / Staging$30-60Less common for teams with continuous stakeholder feedback.
Production (customers affected)$100+Feature flags and fast rollback reduce effective cost for mature teams.

Worked Example: 20-Person Software Team

Inputs

  • Team size: 20 engineers
  • Fully-loaded cost: $200,000/yr
  • Rework rate: 25% (NIST average)

Outputs

Annual rework cost

$1,000,000

At elite level (10%)

$400,000

DORA 2024: Elite Software Team Performance

Deployment Frequency

Elite: Multiple/day

Low: Monthly

Lead Time

Elite: <1 hour

Low: 1-6 months

Change Failure Rate

Elite: <5%

Low: >30%

Time to Restore

Elite: <1 hour

Low: >1 day

Capers Jones: Software Defect Data

Calculate your team's rework cost

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Updated 2 May 2026