Cutover Fundamentals and Execution

Cutover is the process of switching from your legacy accounting system to Light as your primary system. It is a milestone that rewards careful planning, validation, and execution. This guide covers how to run one well.

# What is this page about

This page covers planning a cutover, validating your migrated data before you commit, executing the switch, and stabilising afterwards. It is the process wrapper around the data migration articles, so read those for the mechanics of moving each record type.

On this page

• Cutover overview
• Cutover planning
• Cutover risks and mitigation
• Data migration (covered in detail in other articles)
• Validation checklist
• Establishing Light processes
• Team training and readiness
• Cutover decision criteria
• Executing the cutover
• Post-cutover stabilisation (first week)
• First month-end in Light
• Parallel running (optional but recommended)
• Legacy system archival
• Handling issues post-cutover
• Communication plan
• Stakeholder management
• Post-cutover audit and sign-off
• Measuring cutover success
• Related articles

# Cutover overview

Cutover involves:

1. Planning: Define scope, timeline, risks
2. Data migration: Export, transform, import data to Light
3. Validation: Verify migrated data is accurate
4. Preparation: Train team, establish Light processes
5. Execution: Switch to Light on cutover date
6. Stabilisation: Monitor and resolve post-cutover issues
7. Closure: Ensure legacy system is properly archived

Cutover typically takes 4-8 weeks total.

# Cutover planning

Plan your cutover:

1. Identify cutover date: Typically a month-end (preferred) or quarter-end
2. Define scope: What data transfers? What stays behind?
3. Identify dependencies: What other systems depend on accounting data?
4. Assess risks: What could go wrong? What's the impact?
5. Create timeline: Work backwards from cutover date
6. Assign owners: Who's responsible for each step?
7. Allocate resources: Budget the time and people needed

Document the plan and share it with your stakeholders.

# Cutover risks and mitigation

Common cutover risks:

Create a risk register and mitigation plan.

# Data migration (covered in detail in other articles)

Migrate data to Light:

1. Prepare: Clean up legacy system data, close prior periods
2. Export: Export all data from legacy system
3. Transform: Convert to Light format
4. Import: Import to Light in structured order
5. Validate: Verify GL, AR, AP, customers, vendors
6. Reconcile: Ensure balances match legacy system

See Data migration from QuickBooks and Data migration from E-Conomic for detailed steps.

# Validation checklist

Before cutover, validate:

GL Account Validation:

• Trial balance balances (debits = credits)
• All accounts have correct opening balances
• Account structure matches how your business is organised

Customer/Vendor Validation:

• All active customers and vendors present in Light. Import vendors by CSV at Vendors. Create customers by hand, through the API, or through a CRM integration such as Salesforce or HubSpot, which creates customer records in Light directly. Any customer referenced in a sales invoice import must already exist in Light, since that importer matches against existing records rather than creating them
• Contact information correct
• Vendor payment details (bank account information) set

AR/AP Validation:

• AR aging matches legacy system
• AP aging matches legacy system
• All outstanding invoices/bills present

Account Balances:

• Cash matches bank statements
• AR total matches GL
• AP total matches GL

Fixed Asset Validation:

• Fixed assets entered via journal entries, bills, or sales invoices with a Fixed Asset release template applied on the line
• Fixed asset register reviewed at Accounting → Releases, filtered by Fixed asset type
• Book values match legacy system

Validate using Light's reports at Reports, in particular Trial balance, Aged Accounts Receivable, and Aged Accounts Payable. The Aged AR Detail and Aged AP Detail variants give you the drill-down when a total needs explaining.

# Establishing Light processes

Before cutover, document new processes:

1. Invoice processing: How to create AP/AR invoices in Light
2. Payment processing: How to record customer payments, vendor payments
3. Bank reconciliation: Light's reconciliation process (monthly)
4. GL posting: Journal entry procedures
5. Month-end close: Light's close process and procedures
6. Reporting: How to access and generate reports in Light
7. System access: Who has access to what data
8. Change management: How to request new features or process changes

Document these and share them with your team.

# Team training and readiness

Train your team thoroughly:

1. Leadership training: CFO/finance manager understands full scope
2. Core team training: Daily accounting staff (invoice entry, reconciliation)
3. User training: Anyone who enters data into Light
4. Support training: Who to contact with questions
5. Train-the-trainer: Identify super-users who can help others
6. Practice sessions: Hands-on exercises before cutover
7. FAQs: Document common questions and answers

Schedule training 2-4 weeks before cutover.

# Cutover decision criteria

Before you commit, confirm:

• All data migration validation completed successfully
• GL trial balance balances
• AR and AP aging reports match legacy system
• All integrations tested and working
• Team trained and confident
• Legacy system data backed up
• Stakeholders (auditors, lenders) notified
• IT infrastructure ready

Create a go/no-go checklist.

# Executing the cutover

On cutover day:

1. Final data exports: Export final data from legacy system (as of cutover date)
2. Final import to Light: Import any final transactions
3. Freeze legacy system: Stop posting new transactions to legacy system
4. Announce cutover: Notify team cutover is happening
5. Begin Light posting: All new transactions post to Light
6. Monitor closely: Watch for issues throughout the day
7. Support hotline: Keep people available to help users
8. Communicate status: Keep stakeholders informed

Cutover typically happens late on a Friday, which gives you a full week for stabilisation.

# Post-cutover stabilisation (first week)

In the week following cutover:

1. Monitor system performance: Ensure Light is responsive
2. Track issues: Log all problems reported by users
3. Prioritise issues: Resolve critical issues immediately
4. Communicate: Daily updates to team on status
5. Validate transactions: Sample-check transactions posted in Light
6. Train on-the-job: Address questions as they arise
7. Document workarounds: Where issues remain, document the temporary workaround

Most issues surface in the first week.

# First month-end in Light

Your first close in Light:

1. Month-end procedures: Follow Light's established processes
2. Reconciliations: Bank, AR, AP, GL
3. Accruals: Record accruals per Light process
4. Close: Complete the closing tasks (lock AP, AR, and journal entries, then run FX revaluation), then close the period at Accounting → Accounting periods. Close periods in chronological order, since Light blocks closing a period while an earlier one remains open
5. Reporting: Generate management and statutory reports
6. Validation: Compare results to legacy system results (if available)
7. Adjustments: Record any adjustments needed

This validates that Light processes work correctly.

# Parallel running (optional but recommended)

Run both systems in parallel for 1-4 weeks:

1. Post transactions to both systems
2. Compare results
3. Identify discrepancies
4. Resolve them before you archive the legacy system
5. Switch over fully once the comparison gives you confidence

Parallel running reduces risk and adds work during the transition.

# Legacy system archival

Properly archive the legacy system:

1. Final backup: Create comprehensive backup of legacy system
2. Data exports: Export GL, transactions, reports as PDFs
3. Documentation: Collect all system documentation
4. Access preservation: Maintain login access if needed
5. Retention policy: Decide how long to keep it. Many finance teams keep records for at least seven years, so check your own obligations
6. Secure storage: Store backups securely, encrypted and off-site
7. Decommissioning timeline: Plan when to decommission fully

Keep the archived system for as long as your compliance requirements demand.

# Handling issues post-cutover

If problems surface after cutover:

1. Assess severity: Is this critical or minor?
2. Communicate: Notify affected parties
3. Identify cause: Root cause analysis
4. Develop solution: Fix the issue
5. Implement: Deploy fix
6. Validate: Verify fix works
7. Prevent recurrence: What can we do differently?

Have a rapid response process.

# Communication plan

Maintain regular communication:

1. Pre-cutover: Regular updates on progress
2. Cutover week: Daily status updates
3. First month: Weekly updates
4. Post-first month: Monthly updates as issues resolve

Use email, team meetings, or shared dashboards to communicate.

# Stakeholder management

Keep key stakeholders informed:

• CFO/Controller: Overall responsibility for cutover success
• Finance team: Daily users affected most
• IT: Infrastructure and technical support
• External auditors: May need to validate migration
• Lenders: If required by agreements
• Investors: If material to business

Tailor communication to each stakeholder group.

# Post-cutover audit and sign-off

Document cutover completion:

1. Cutover report: Document what was migrated, what wasn't, issues encountered
2. Validation results: Document all validation performed
3. Sign-off: Finance leadership approves cutover completion
4. Lessons learned: What went well? What could be better?
5. Archive documentation: Store all cutover documentation for audit trail

This provides evidence of proper cutover.

# Measuring cutover success

Evaluate cutover success:

1. Data accuracy: Is GL accurate? Do reports match expectations?
2. System adoption: Are users comfortable in Light?
3. Process efficiency: Are month-end closes faster? More accurate?
4. Compliance: Are we meeting audit and regulatory requirements?
5. Issues: How many critical issues? How quickly resolved?
6. Cost: Was cutover within budget?
7. Timeline: Did we hit the planned cutover date?

Document these metrics as part of your cutover report.

# Related articles

• Data migration from QuickBooks
• Data migration from E-Conomic
• Data import and migration tools
• Audit-ready record keeping
• Go-live readiness