Love Karbon, Ready to Leave, but Afraid to Move? Migrate Between October and January

You have seen Karbon. You like it. The partners agree the firm has outgrown its practice management system. And nobody wants to be the one who schedules the move.

That hesitation is reasonable, and it has a fix. Here is why we plan Karbon migrations between October 15 and January 31, and how we run them alongside Karbon's own implementation team.

Practice management is the system everyone in the firm uses all day. Staff record time in it, managers run work from it, administrators bill from it, and partners read WIP and AR from it. That reach makes a better system one of the largest productivity gains a firm can make.

It is also why firms stay put. A migration changes client records, time entry, billing, open WIP, receivables and documents at once. Done mid-year, it means running two systems through a deadline while reconciling both.

The answer is not to avoid the move. It is to put the move where the calendar can absorb it.

Why the migration window is October 15 to January 31

For most tax-focused CPA firms, the best time to migrate to Karbon is between October 15 and January 31, because that is when the firm has administrative time and the least live work.

October 15 is the extended due date for Form 1040 and calendar-year Form 1120 returns (IRS Publication 509). After it, most engagements are finished. By the end of January the pace is back: W-2 and 1099-NEC filings are due at the turn of the month, and the March business deadlines are close. The months in between leave room to map the data, unit-test the setup and rehearse the load.

A mid-year move is harder. Time and invoices are posted every day, every reconciliation is done while the numbers are still moving, and two systems have to stay in step through extension season.

Karbon's own implementation timelines fit inside the window. Its Guided Plus Implementation runs over eight weeks, and its Billing & Payments Implementation goes live in three to four.

Two caveats. A firm with a large nonprofit or fiscal-year audit practice should shift the window to its own low point. A larger firm should run the evaluation over the summer, so October starts with the decision made.

When	What happens
Summer, before October 15	Technology stack evaluation and the decision to move
October to November	Data cleanup and mapping, work templates, access controls, trial account
November to December	Test loads of clients, work and documents
The day before a holiday	Cutover: open WIP and AR move, and the old system is frozen
January	Parallel run on old receivables, staff support
When the old AR has cleared	The old system is backed up and turned off

Technology stack evaluation: decide before anything moves

Some firms come to us certain they want Karbon. Others are not sure it is the right system at all. Either way, the project starts with a technology stack evaluation, not a data export.

We map the systems the firm runs today, the dependencies between them, the processes, and where work stalls. Then we lay out the same firm on Karbon, with the time saved, the cost compared, and what Karbon will not replace. The tax software, for one, stays where it is. We usually arrange a demo with the Karbon team built around the firm's own scenarios.

Sometimes the right answer is to stay, and the evaluation should be able to say so.

Migration planning and configuration

Most of the hours in a Karbon migration are spent here, before any data moves.

Data cleanup and data mapping

Old systems collect duplicates, inactive clients, and fields that mean different things to different offices. We clean the data, map every field to its place in Karbon, and test the mapping in a sample migration.

Karbon's import file has its own conventions. It recommends, for example, setting up a married couple as an organization with each spouse as a related person (Karbon help: Import client data). That is a five-minute decision on paper, and a long afternoon once a few thousand records are in.

Work templates: the step most firms miss

Work templates are the firm's standard operating procedures in Karbon, and firms most often leave them too late. Some are administrative, like client onboarding and engagement letters. Most belong to a service line, so the department leaders from administration, tax, assurance and client accounting services (CAS) build their own, with us, before the migration.

Karbon gives a second reason to finish them early. Templates must be published before work is created in bulk, and role assignments are set at that point. Afterwards, roles can only be added one work item at a time (Karbon help: Create work items in bulk).

Access controls

If each office should see only its own clients, the contacts and their client teams have to be set up that way before the data lands. Karbon sets a privacy level on each contact. Public contacts are open to everyone, private contacts are limited to the client team, and hidden contacts are also left out of everyone else's searches (Karbon help: Sensitive data in Contacts).

Assigning that across a few thousand contacts is a design exercise. It is far easier in a spreadsheet than record by record later.

Trial account and contracts

Karbon's standard trial runs two weeks, and in our experience it can sometimes be extended by agreement. We use it as the firm's working environment for template building and test loads before the firm commits to the full subscription.

The current vendor's renewal date and notice period get lined up with the cutover too, so the firm does not pay for two systems longer than it needs to.

Data migration sequence: four loads, in order

Karbon's import guide sets the order: client data, then processes, then work (Karbon help: Import process overview). A full migration adds documents, then open WIP and AR. Each load depends on the one before it.

We work alongside Karbon's implementation team, not in place of it, and we recommend using it. Karbon's own implementation services cover what goes into Karbon: imports, templates, settings and training. We cover what sits outside it. That means getting the data out of the old system, cleaned and tested, plus the documents, the tax software connections, the cutoff, and the reconciliation that proves nothing was lost.

1. Clients

Karbon's direct upload on the Contacts page brings in the basics: names, emails, phone numbers and addresses (Karbon help: Import your client list). A full client record, with client IDs, fiscal year ends, client groups and the people in each organization, goes in one of two ways.

The first is Karbon's Excel template, which anyone on the admin team can work in. Karbon's staff validate each file by hand and return it with corrections. In our experience a round takes one to two days, so we plan the schedule around it.

The second is Karbon's public API, through a loader we have built and used across Karbon migrations (more on Karbon's API). A load runs immediately, so a test migration can be run, checked with the firm's team, and run again the same day. We use it when the timeline is tight or the firm wants several rehearsals.

2. Work items

Karbon offers free self-service bulk work creation, and an assisted service as a paid add-on (Karbon help: Create work items in bulk). We walk the firm's team through the self-service screens, including naming conventions, or create the work through the API when the firm wants a particular structure.

3. Documents

Karbon connects contacts and work items to OneDrive or SharePoint folders. Moving the files into those folders happens outside Karbon, which has no bulk upload (Karbon help: Document storage FAQ).

We set up the destination SharePoint site, run a unit-test migration on a couple of clients, then move the rest and link each Karbon contact and work item to its folder in bulk. On one enterprise project, 1.2 million documents for about 11,000 clients moved from GoFileRoom to SharePoint, and API tooling cut the projected timeline from 12 weeks to two or three. More in why firms move from a legacy DMS to SharePoint and planning a GoFileRoom to SharePoint migration.

4. Open WIP and AR

Only open WIP and open AR move. Every imported invoice arrives as open, and so does every WIP balance. Paid invoices and billed time stay in the old system.

Many firms ask for two years of history. Plan for open balances only. The two systems structure time, invoices and payments differently, so history stays in the old system and its backup.

Karbon's billing package includes "one WIP and Open AR import, completed by a Karbon Specialist" and validated with the firm (Billing & Payments Implementation). Turnaround is mostly within two days. We prepare the template from the old system's open balances, and after the import we tie Karbon's totals back to the old system's reports.

Cutover and system freeze

Everything above leads to one date: the cutoff, after which nothing new is posted in the old system.

Set it around billing, not the project plan. The right cutoff falls just after the period's final invoices go out, when unbilled WIP is smallest. We usually aim for the day before a holiday, so WIP and AR move while people are out.

The cutoff also needs a freeze, and this is where firms get surprised. Most legacy practice management systems let users post or adjust transactions with an earlier date. Day to day, that is useful. In a migration, it breaks the reconciliation.

The firm runs its WIP and AR reconciliation the day before the migration. Three weeks later it runs the same reports with the same date parameters, and the totals have moved. Nobody broke a rule. Someone found a few hours from early December and posted them, because the system let them.

So the firm agrees in advance. From the cutoff date the old system is frozen, and only a few administrators can post in it, only to close out WIP and AR.

Parallel run and decommissioning

The old system does not switch off the day after cutover. Clients pay the invoices they received, and those came from the old system. For a while, the firm records each payment in both systems so the invoice closes in both, usually by hand. Once the old open invoices are paid and the remaining WIP clears, the legacy system can be turned off.

A longer parallel run is possible, but only by design, and it is not simple. Karbon's API can list open invoices and record a manual payment against one (Karbon developer guide: Invoices and payments), so a payment recorded in the old system can be applied to the same invoice in Karbon automatically. We build that sync when a firm needs it, as a deliberate choice rather than a default.

Before retiring the old system, back it up and plan a bridge for reports that need history, such as multi-year realization. This part is particular to each firm, so we work hands-on with the firm's team and reconcile until the numbers agree.

Where a migration goes wrong, and the control for each

Every step above exists to control a specific risk.

Risk	Control
Moving to the wrong system	A technology stack evaluation that can recommend staying
Bad data loaded into Karbon	Cleanup, mapping and a sample migration; the firm approves each test load before the full one
The wrong people seeing a client	Privacy levels and client teams designed before import
Work created without its roles	Templates and role assignments finished before bulk work creation
Documents missing their client link	A unit-test migration on a few clients, then every folder linked in bulk
WIP and AR that no longer tie out	A cutoff after final billing, reconciliation before and after, and a freeze on the old system
Payments recorded in one system only	A parallel run until the old AR clears, or a designed payment sync

Roles and responsibilities

Silver Sea is listed in Karbon's Partner Directory as a Karbon Certified Expert. In a typical migration, the work divides like this.

Phase	The firm	Karbon	Silver Sea
Evaluation	Shares processes, costs and problem areas; leadership decides	Product demo and trial account	Technology stack evaluation, with time and cost compared
Planning and configuration	Department leaders build work templates; approves the security model	Implementation services: setup, best-practice templates, training	Timing plan, data cleanup and mapping, template workshops, access-control design, sample migration
Clients and work	Approves each test load	Import templates and validation; self-service and assisted bulk work creation	Data extraction, API-based test loads, help with the self-service screens
Documents	Approves the folder structure	OneDrive and SharePoint folder connections	SharePoint setup, test migration, full migration, bulk folder links
Open WIP and AR	Runs the final billing; agrees the cutoff and the freeze	Open WIP and AR import by a Karbon Specialist	Cutoff planning, template preparation, reconciliation before and after
Parallel run and retirement	Records payments; confirms the old AR has cleared	Ongoing support	Payment sync where designed, legacy backup, reporting bridge

The calendar is the plan

Firms that love Karbon but stay put are rarely afraid of Karbon. They are afraid of everything changing at once, in front of a team learning new screens during a deadline.

The October-to-January window puts it in order. The decision comes before the window opens, the setup happens while the firm has time, and the data moves in a fixed order. The cutover lands on a holiday, and the old system retires when its last open invoice is paid.

The window has an edge, too. A firm that decides in March is looking at next October.

If your firm is weighing a move this season, start with the technology stack evaluation. Book a discovery call and we will look at your current setup and whether this window still works. How we run Karbon migrations is also on our Karbon page.

Questions firms ask

When is the best time to migrate to Karbon?

For most tax-focused CPA firms, between October 15 and January 31. The extended filing deadline has passed, most engagements are finished, and there is time to set up and test before W-2 and 1099 season. Firms with nonprofit or fiscal-year audit peaks should shift the window to their own low point.

Can we bring historical WIP and AR into Karbon?

Only open balances move. Every imported invoice arrives as open, and paid invoices and billed time stay in the old system. Back the old system up and plan how multi-year reports will be produced.

Does Karbon migrate our documents?

Karbon connects contacts and work items to OneDrive or SharePoint folders, but it has no bulk upload, so moving the files is a separate workstream, usually into SharePoint.

How long does a Karbon migration take?

It depends on the firm's size and how much is moving. Karbon's Guided Plus Implementation runs over eight weeks and its Billing & Payments Implementation over three to four. We plan the whole project inside the October-to-January window, with the evaluation done beforehand.

Do we have to run two systems at the same time?

Briefly. Clients pay the invoices the old system issued, so payments are recorded in both systems until the old open AR clears. A longer parallel run is possible with an API-based payment sync, but it has to be designed.