Starting a family office is a significant step in managing family wealth, but most people don’t realize that setting up the books, banking, connected accounts, and reporting is a distinct project from establishing the legal entity. It has its own sequence and set of decisions around it, and rightfully deserves its own project during the stand-up process.
This guide walks through the infrastructure for starting a family office, including what to build, in what order, what tends to go wrong, and which processes to put in place to prevent errors.
Many families skip straight from "we formed an LLC" to "we're managing $150 million across twelve entities in a spreadsheet,” and this guide will help you create the right steps to make that jump.
What financial infrastructure a family office needs
At a minimum, a functioning family office needs:
An accounting structure that mirrors its legal entities
A general ledger system built for multi-entity consolidation
Bank and custodian connections feeding into that ledger
A bill pay and approvals workflow, a defined month-end close process
Audit trails that satisfy both the family and any external auditors or tax preparers
Permissions-based settings that can be adjusted as needed
Each of these is a separate build, and each one gets harder to retrofit the longer a family office runs on ad hoc tools like QuickBooks or Sage.
Why this part of the conversation gets skipped
Most family office formation content comes from three sources: private banks, law firms, and fund administrators. Private banks focus on investment strategy and governance because these are what lead to an advisory relationship. Law firms focus on entity structure and compliance because that's their function, while fund administrators focus on LP reporting and back-office outsourcing — because that's their product.
None of these sources are wrong to focus where they do, and in these cases, they’re specialists for a reason. However, this results in answers about "how to start a family office" that treat the accounting and operational layer as an afterthought — usually a single line about needing "robust technology" or "reporting systems," with no detail on what that actually entails.
Families end up building the legal and governance side deliberately and the financial infrastructure side reactively, and by then, it tends to be too late. When the spreadsheets are scattered and stop working altogether, it can be tough to backtrack, and this is why getting the infrastructure right the first time makes all the difference.
Map your legal entities to an accounting structure
Your attorney will set up the LLCs, trusts, and holding companies that make up the family office's legal structure. That structure does not automatically translate into an accounting structure, and treating the two as identical is a very common early mistake.
Each legal entity typically needs its own set of books, but entities that share ownership, engage in intercompany transactions, or roll up into a consolidated view need a chart of accounts designed with consolidation in mind from the start. Decide early:
Which entities need standalone financial statements versus which only need to feed a consolidated view?
How intercompany loans, shared expenses, and management fees will be tracked and eliminated at consolidation?
Whether the chart of accounts will be standardized across entities or customized per entity type (operating business, investment holding company, real estate LLC, trust)?
Retrofitting a chart of accounts across a dozen entities after two years of inconsistent bookkeeping is significantly more expensive than designing it correctly before the first transaction is recorded.
Choose a general ledger system before you outgrow one
Most family offices start on QuickBooks. It’s not a bad place to start, but it’s designed for smaller businesses. Though it handles single-entity accounting well, most family offices outgrow it very quickly. It was not built for multi-entity consolidation, intercompany eliminations, or the reporting a family office eventually needs across a dozen or more entities, so it becomes a nightmare to use after some time.
The general ledger decision matters because switching systems after two or three years — once entities, historical data, and staff workflows are built around a tool that can't scale — is disruptive and expensive. When evaluating a general ledger, the questions that matter most are:
Does it support native multi-entity consolidation, or does consolidation happen manually outside the system?
Can it handle intercompany transactions and eliminations without manual journal entries in a spreadsheet?
Does it integrate with the banks, custodians, and investment platforms the family office already uses?
What does the audit trail look like, and does it satisfy the family's external auditor or tax preparer?
Purpose-built family office general ledgers like SumIt exist for this reason. Evaluating one earlier, even if the family office is still small enough to run on general-purpose accounting software today, avoids a costly migration later.
Even if you don’t make the transition immediately, you should be forward-thinking for when you eventually do need to switch.
Connect banking, custody, and cash management
Once the accounting structure and system are in place, the next layer is connecting the accounts that generate the transactions. This typically means bank accounts per entity (or a defined subset of entities), custodian and brokerage feeds for investment accounts, and a cash management approach for moving money between entities without creating a compliance or bookkeeping mess.
Decide early how cash sweeps between entities will be documented — as intercompany loans, distributions, or capital contributions — because this decision affects tax treatment and needs to be consistent.
Build the billpay and accounts payable workflow
Family offices handle a wide range of payments: vendor invoices, staff payroll, family member distributions, philanthropic giving, and personal expenses routed through the office. Billpay is often a single point of failure, as typically, one bookkeeper or the founder's assistant will have unchecked access to move money.
A functioning bill pay process needs, at minimum, a documented approval chain before payment, segregation between the person who initiates a payment and the person who approves it, and a consistent method for categorizing expenses to the right entity.
This is also where family offices frequently underestimate risk. Family offices are disproportionately targeted by payment fraud because of the volume of transfers and the informal processes many run on, so this is important to prevent before it happens, period.
Establish a month-end close process
The month-end close process turns raw transactions into financial statements the family can use to make decisions. Without a defined close process, "monthly financials" tend to slip into whatever the bookkeeper gets to, and by the time reports are finalized, they're too stale to inform anything. Then, you’re stuck in a vicious cycle of re-running data that’s no longer usable.
A reasonable close process for a multi-entity family office includes a fixed close calendar, entity-level reconciliations completed before consolidation, a documented method for intercompany eliminations, and a review step before financials are considered final. The specific cadence matters less than having a consistent one followed every month, since inconsistency is what makes year-end and audit work painful later.
Put audit trails and controls in place from day one
Family offices are private, but that doesn't mean they're exempt from the controls a public company or fund would need. Most family offices eventually face some combination of an external auditor, a tax preparer who needs clean records, a bank underwriting a loan against family assets, or, in less fortunate cases, a fraud investigation.
Segregation of duties, documented approval workflows, and a system that logs who changed what and when are not optional. The hard truth is that they’re considerably easier to build in from the start than to reconstruct after the fact. Nobody likes to think that they’ll ever be in a situation where an audit trail is needed, but it happens, and you should be prepared.
Decide what to build in-house vs. outsource
Few family offices need a full accounting department on day one, and a majority of them run with a small handful of dedicated employees for years. The more relevant question is which functions require in-house judgment and which can be handled by an outside CPA firm, bookkeeper, or outsourced controller.
As a general pattern: bookkeeping and transaction coding are the most commonly outsourced early on, tax strategy typically stays with an outside CPA firm regardless of family office size, and the controller or finance lead role tends to move in-house once the family office is running enough entities that continuity and institutional knowledge become more valuable than flexibility.
A realistic timeline
Legal formation of a family office can take weeks. Building the financial infrastructure well typically takes longer, and rushing it tends to produce the exact problems this guide addresses. A reasonable sequence looks like:
Finalize the legal entity structure with counsel
Design the accounting structure and chart of accounts around that legal structure
Select and implement a general ledger system built for multi-entity consolidation
Connect banking and custodian feeds
Build and document the bill pay workflow and approval chain
Define the month-end close calendar and process
Decide on in-house versus outsourced roles for ongoing bookkeeping, controllership, and tax
Families that follow roughly this order tend to avoid the costly rebuild that comes from bolting infrastructure on after the fact.
Frequently asked questions about how to start a family office
What accounting software do family offices use? Many family offices start on general-purpose software like QuickBooks and migrate to a purpose-built, multi-entity general ledger once they outgrow single-entity accounting — typically once they're managing multiple LLCs, trusts, or investment entities that need to consolidate into one view.
How long does it take to set up a family office's financial infrastructure? Legal entity formation can happen in weeks. Building out the accounting structure, general ledger, banking connections, and close process properly typically takes longer and is worth treating as its own project rather than an afterthought to legal formation.
Does a family office need a dedicated controller? Not necessarily at the outset. Many family offices start with outsourced bookkeeping and an external CPA firm, and bring a controller or finance lead in-house once the number of entities and transaction volume make continuity more valuable than flexibility.
What's the difference between a family office's legal structure and its accounting structure? The legal structure — LLCs, trusts, holding companies — is set up by counsel and governs ownership, liability, and tax treatment. The accounting structure is how those entities are represented in the general ledger, including the chart of accounts and consolidation logic, and it needs to be designed deliberately rather than assumed to mirror the legal structure automatically.
Conclusion
Most of the decisions above don't need to be finalized on day one, but they're worth understanding before the family office is running enough entities that changing course gets expensive. The general ledger decision, in particular, is one families often revisit once they outgrow QuickBooks — at that point, it's worth looking at systems built specifically for multi-entity family office accounting, like SumIt, to make the infrastructure as simple yet powerful as possible.
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