Accounting Software Implementation Checklist

Interview the controller, AP/AR leads, and operations to capture today's pain points: days-to-close, manual reclasses, COA bloat, missing dimensions, broken bank feeds, AJEs that get re-keyed every month. This list becomes the configuration brief — without it the new system inherits the same mess.

Match scope to platform: QBO/Xero for single-entity SMB, Sage Intacct for multi-entity dimensional reporting, NetSuite for ERP-adjacent needs. Decision drives downstream configuration — dimensions exist in Intacct/NetSuite but only as classes/locations in QBO.

If the client has subsidiaries, holding-cos, or foreign operations, consolidation and FX revaluation must be designed in upfront. Adding a second entity to a single-entity QBO file later is painful — it usually means a re-implementation.

Name the implementation partner, internal project owner (usually controller), AP/AR leads, and IT contact. Engagement letter should fix scope, fee, cutover date, and a change-order clause — implementations are scope-creep magnets when payroll, inventory, or T&E surface mid-build.

Use the platform's industry template as a starting point, then prune. Most legacy COAs have grown to 400-800 accounts because tracking requests turned into new GL accounts; in the new system, push that detail into classes, locations, customers, or dimensions instead.

Define the reporting cuts management actually wants: department, location, project, fund. In Intacct/NetSuite these are dimensions; in QBO they're classes and locations. Lock down which dimensions are required at transaction entry — optional dimensions get skipped and reports break.

Pull the 50-state revenue summary and identify any state above the $100K / 200-transaction Wayfair threshold. Connect Avalara or TaxJar if filing in 5+ states; native tax tables work for 1-3 states. Register before activating tax in any new state.

Enforce segregation of duties: AP clerk enters bills, controller approves, CFO approves over a threshold (commonly $5K or $10K). Set bank-rec and journal-entry permissions to controller-only. Document the matrix — auditors ask for it on the SOC walkthrough.

Set up the consolidation entity, intercompany accounts, and FX revaluation rules. Define which sub-ledgers post intercompany automatically (Intacct ICT module) versus manual elimination JEs at month-end. Test with a sample intercompany invoice before cutover.

Pull a frozen TB as of the cutover date from the legacy system, plus open AR aging, open AP aging, fixed-asset roll-forward, and loan balances. These are the source-of-truth artifacts that will be tied to in the new system.

Clean the lists before import — duplicate vendors with trailing whitespace, customers marked active that haven't paid in three years, items with no GL mapping. Confirm W-9 status on every vendor flagged as 1099-eligible; missing W-9s become a January problem.

Post the opening JE so the new system's TB matches the legacy TB to the penny on cutover date. Open AR and AP must be loaded as individual transactions (not lumped) so aging and customer/vendor statements are correct day one.

Connect every operating, payroll, and credit-card account through Plaid or direct feed. Set the feed start date to the cutover date — pulling history before cutover creates duplicate transactions against the loaded opening balance.

Wire up Gusto/ADP/Rippling for payroll JE sync, Bill.com or Ramp for AP, Dext or Hubdoc for receipts. Map each integration to the correct GL accounts and dimensions — default mappings post payroll to a single 'Wages' account and lose department detail.

Close the same period in both systems. Compare TB account-by-account, P&L by department, and balance sheet line items. Tolerance for variance should be zero on balance-sheet accounts and within rounding on P&L; any larger variance means a mapping or opening-balance issue.

Variances usually trace to one of: COA mapping mismatch, missed opening AR/AP transactions, sales-tax code applied differently, or a class/dimension that's required in one system and optional in the other. Document each variance and the fix; do not move to go-live with unresolved differences.

Rebuild the management report pack — P&L by department, balance sheet, cash flow, AR aging, KPI dashboard — in the new system and compare formatting and totals to the legacy version. Stakeholders will reject a system that produces 'different' numbers even when the new ones are correct.

Run role-specific sessions: AP clerk on bill entry and approval routing, AR on invoicing and collections, controller on bank rec and JE posting. Record the sessions and post written SOPs to the document portal — staff turnover within 12 months is the norm and oral training does not survive.

On cutover, set a close date with password lock in the legacy system so no one books retroactive entries that drift the opening balance. Communicate the cutover to AP, AR, and operations the day before — late vendor bills are the most common source of post-cutover noise.

Day-after cutover: verify every bank feed pulled overnight, every payroll/AP/expense integration posted its first transaction correctly, and every user can log in with their assigned role. Catch broken integrations before the first weekly AP run, not at month-end.

First close will take roughly 1.5x the legacy system. Implementation partner shadows the controller through bank rec, sub-ledger tie-out, AJEs, and reporting. Capture every workaround and unexpected behavior in a punch list for the retrospective.

Review the punch list with the controller and partner: configuration items to adjust, training gaps to fill, integrations to refine. Schedule a follow-up at the 90-day mark to revisit anything that only surfaces over a full quarter (sales-tax filings, payroll quarterlies, intercompany eliminations).