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Replatforming Programme Planning

Ecommerce Replatforming Timeline

A realistic roadmap for planning, selecting, implementing and launching a new ecommerce platform without underestimating the work between business case and go-live.

A replatforming timeline is not just a delivery plan. It is a sequence of decisions.

The most reliable programmes do not rush from platform selection into build. They move through business case, discovery, requirements, governance, partner selection, integration, testing, migration and controlled launch.

Roadmap

The typical ecommerce replatforming journey

Every organisation is different, but most successful programmes move through a similar set of stages. The sequence matters because each stage reduces uncertainty before the next investment decision is made.

01
Business Case
2–4 weeks
02
Discovery
3–6 weeks
03
Requirements Definition
3–5 weeks
04
Platform Selection
4–8 weeks
05
RFP and Partner Selection
4–8 weeks
06
Programme Planning
2–4 weeks
07
Design, Build and Integration
10–24 weeks
08
Testing and Migration
4–8 weeks
09
Go-Live
1–2 weeks
10
Hypercare and Optimisation
4–12 weeks
Programme Phases

A practical phase-by-phase timeline

Use this as a planning reference rather than a promise. Duration depends on scope, systems complexity, product data, internal availability, governance and the number of markets or brands involved.

01

Business Case

Define why the organisation needs to replatform and what commercial, operational or strategic constraint the current ecommerce estate is creating.

2–4 weeks
Key outputs
Business caseExecutive sponsorBudget rangeSuccess criteria
Common pitfalls
  • Starting with platform preference rather than business need
  • Underestimating internal resource
  • Treating the project as a website refresh
02

Discovery

Map the current operating model, customer journeys, systems, data, pain points and business requirements before solution decisions are made.

3–6 weeks
Key outputs
Current-state assessmentStakeholder interviewsProcess mappingInitial risks and dependencies
Common pitfalls
  • Stakeholders unavailable
  • Hidden operational complexity
  • Requirements being captured too narrowly
03

Requirements Definition

Translate business objectives into prioritised commercial, operational, technical and customer experience requirements.

3–5 weeks
Key outputs
Prioritised requirementsIntegration requirementsData requirementsMVP definition
Common pitfalls
  • Everything becomes a must-have
  • Requirements written for vendors rather than business outcomes
  • Insufficient attention to ERP, pricing or product data
04

Platform Selection

Assess which ecommerce platform options are genuinely suitable for the organisation's business model, complexity and future operating requirements.

4–8 weeks
Key outputs
ShortlistPlatform comparisonDecision criteriaRecommended platform direction
Common pitfalls
  • Choosing based on demos
  • Overweighting brand familiarity
  • Ignoring total cost of ownership
05

RFP and Partner Selection

Select an implementation partner using clear scope, evaluation criteria, commercial expectations and governance requirements.

4–8 weeks
Key outputs
RFPVendor scorecardAgency selectionCommercial proposal
Common pitfalls
  • Comparing inconsistent proposals
  • Selecting on day rate rather than delivery confidence
  • Allowing agencies to define the problem
06

Programme Planning

Create the delivery structure, governance cadence, project plan, risk register, resource plan and launch approach before build begins.

2–4 weeks
Key outputs
Project planGovernance modelRisk registerResourcing plan
Common pitfalls
  • Build begins before ownership is clear
  • No realistic dependency management
  • No escalation path for scope or budget decisions
07

Design, Build and Integration

Design and build the new ecommerce experience, integrate core systems and configure the platform around agreed business requirements.

10–24 weeks
Key outputs
UX/UIConfigured platformERP/PIM/payment/search integrationsContent and data preparation
Common pitfalls
  • ERP complexity discovered too late
  • Product data not ready
  • Design decisions made without operational validation
08

Testing and Migration

Validate functionality, integrations, data, SEO migration, payment flows, order processing and business readiness before launch.

4–8 weeks
Key outputs
UATSEO migration planRedirect mappingData migrationLaunch readiness checklist
Common pitfalls
  • Business users too busy to test
  • SEO treated as a late task
  • Incomplete data or catalogue validation
09

Go-Live

Launch the new platform safely, monitor critical flows and manage immediate operational, technical and customer-facing issues.

1–2 weeks
Key outputs
Launch planRollback planMonitoringIssue triage
Common pitfalls
  • Launch date chosen for politics rather than readiness
  • No ownership of go-live decisions
  • Insufficient monitoring of orders, payments and redirects
10

Hypercare and Optimisation

Stabilise the new ecommerce estate, resolve defects, review performance and move into continuous improvement.

4–12 weeks
Key outputs
Hypercare supportPerformance reviewDefect backlogOptimisation roadmap
Common pitfalls
  • Project team disbands too early
  • No benefit tracking
  • Optimisation budget disappears after launch
Duration

How long should ecommerce replatforming take?

The honest answer is that duration follows complexity. A simple retail migration is very different from a B2B manufacturer with ERP integration, customer-specific pricing, trade accounts and complex product data.

Small retailer
4–6 months

Relatively simple catalogue, limited integrations and modest operational complexity.

Mid-market manufacturer
8–12 months

B2B requirements, ERP integration, customer-specific pricing, product data and internal process change.

Complex international B2B
12–18 months

Multiple markets, complex integrations, trade accounts, PIM, pricing, fulfilment and governance requirements.

Dependencies

The dependencies that control the timeline

Replatforming timelines rarely slip because one task took longer in isolation. They slip because upstream decisions, data, systems or people were not ready when later stages depended on them.

01
Business case
02
Discovery
03
Requirements
04
Platform selection
05
Partner selection
06
Governance
07
Build and integration
08
Testing and migration
09
Go-live
10
Hypercare
Project Risk

Where ecommerce replatforming timelines usually slip

These are the areas that most often turn an optimistic plan into a delayed programme. They should be actively managed from the beginning rather than discovered near launch.

DiscoveryStakeholders are unavailable or requirements are captured too superficially.
ERP integrationHidden order, pricing, stock or customer account dependencies emerge late.
Product dataCatalogue structure, attributes, images or taxonomy are not ready for migration.
SEO migrationRedirects, metadata, URL structure and content changes are considered too late.
TestingBusiness users do not have enough time to complete meaningful UAT.
LaunchThe date is fixed before operational readiness has been proven.
FAQ

Common questions

Short answers to common questions about ecommerce replatforming timelines, project phases, testing, ERP dependencies and go-live planning.

01 of 07

A simple ecommerce replatform may take 4–6 months, while a mid-market manufacturer with ERP integration, product data complexity and B2B requirements should typically expect 8–12 months. Complex international or multi-channel programmes can take 12–18 months.

Next Steps

What to read next

Use the timeline alongside the other planning resources in the ecommerce replatforming library.

Independent Advice

A realistic timeline protects the investment before the project begins.

Right Partners helps manufacturers and retailers plan ecommerce replatforming programmes with clear governance, realistic sequencing, platform-independent advice and commercial discipline.

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