Bookkeeping checklist for freelancers: what you need to have in order

The moment you register with the Chamber of Commerce as a freelancer, the legal bookkeeping obligation automatically applies. That means keeping records that show your rights and obligations at any given moment: what you've invoiced, what you've spent, and how much VAT you owe or can reclaim. The exact rules for what your records must contain are described on KVK.nl — worth reading through once properly if you're just starting out.

If you're new to this: bookkeeping for beginners sounds more complicated than it is. At its core, freelance bookkeeping comes down to four habits you keep from day one.

• Keep business and personal separate. Open a separate business account, even if that isn't strictly required for a sole proprietorship. It saves hours of sorting at year-end and avoids arguments with the tax authorities about what was and wasn't business-related.
• A complete VAT record. Every invoice you send or receive needs to be traceable, including the VAT amount. This is the foundation for your periodic VAT return.
• A 7-year retention obligation. You keep invoices, receipts, contracts and bank statements for at least seven years. That applies to digital documents too — a scanned receipt counts just as much as the paper original.
• Consistency. Whether you start with a spreadsheet or dedicated accounting software, make sure you have one fixed place where everything comes together. If you're after structure, you don't need an expensive bookkeeping course for freelancers — the right software teaches you the basics as you go.

slimzaak is built for freelancers who want this foundation in order without having to learn a full accounting package: it's the place where your invoices, expenses and VAT overviews come together, so you meet your bookkeeping obligations without it eating up half your week.

Invoices are the foundation of your bookkeeping: without correct, VAT-compliant invoices, your books don't add up. In slimzaak you create invoices automatically or manually, with the right VAT applied — whether that's standard Dutch VAT or, for consumer sales in other EU countries, the OSS scheme. You create quotes in the same tool, so an accepted quote flows straight into an invoice with one click.

Two things that often get overlooked:

• Credit notes. If you need to correct or credit an invoice, don't do it with a loose Word document — use a proper credit note that meets the same requirements as the invoice itself. slimzaak generates credit notes automatically from the original invoice.
• Sales via bol.com, Amazon, Shopify or WooCommerce. If you sell through a marketplace or webshop, you don't need to manually re-type orders into invoices — the integrations handle that for you.

Invoicing is the part of your bookkeeping where you gain the most time back: once it's set up, you'll barely need to look at this step again.

Receipts are the classic pitfall of freelance bookkeeping: a crumpled one in your pocket, a photo on your phone you can never find again, or a fuel receipt that fades before you get around to processing it. In slimzaak you solve this with AI scanning for expenses and receipts: you take a photo or upload the receipt, and details like amount, VAT, supplier and date are read automatically and logged as an expense.

That doesn't just save time — it's also a direct part of meeting your retention obligation: every scanned receipt stays retrievable, even once the paper original has long since faded. Want to understand how expenses, receipts and credit notes fit together to keep your bookkeeping airtight? Read our explainer on cash books and credit notes in freelance bookkeeping.

One part that's missing from most checklists but has a direct effect on your tax return: time tracking. Search for time tracking for freelancers and you'll quickly land on the hours criterion — to qualify for the self-employed tax deduction, you need to spend at least 1,225 hours a year on your business within a calendar year. That's not just billable hours or client calls: it covers all the time you can demonstrably show you spent on your business, from acquisition and admin to the actual work itself.

The problem is that if the tax authorities audit you, they'll ask for evidence, and "I'm sure it was more than 1,225 hours" isn't evidence. What does work is a simple log you keep throughout the year: a spreadsheet with date, activity and number of hours, or a separate time-tracking app if you'd rather not log it manually. What matters most is that you keep it as you go, not that you reconstruct it afterwards. Keep this separate from your invoicing and expenses — it's a different kind of record, with a different purpose: proving your self-employed status, not billing itself.

If you drive for your business, sooner or later the question comes up: put the car on the business, or use your personal car for business trips? In short: if you register the car in the business's name and also use it privately, you'll deal with the private-use car tax addition — a percentage of the list price added to your profit. If you mainly drive for business in a personal car, you'd typically use a mileage allowance instead of a tax addition.

Which route works out better for you depends on how much you drive, the type of car, and how much of that is business use — that's a calculation best worked out with an accountant or the tax authorities' own calculation tools.

What slimzaak does solve for you: the individual business car costs you incur — fuel, maintenance, a car wash before a business meeting — you simply log as a receipt in the expenses feature, just like any other business expense. Keep in mind that slimzaak doesn't calculate the tax addition and doesn't track mileage; that stays a separate part of your bookkeeping, alongside expense tracking.

At the end of the financial year, every freelancer faces the same moment: closing the books. If you run a sole proprietorship, formally it's not a full annual account like a limited company files, but a profit-and-loss statement that becomes part of your income tax return. Preparing the annual accounts doesn't have to be complicated once your bookkeeping has been in order all year: you prepare it yourself using accounting software, or you have an accountant do it.

What you need for it isn't anything new — it's the same building blocks you've been keeping all year. Your revenue from invoices, your expenses from receipts, and your VAT overviews per quarter. slimzaak keeps these pieces organized for you all year round, so at year-end you're not chasing down loose invoices and receipts — you simply pull up the overview.

One thing worth being clear about: slimzaak doesn't prepare annual accounts or a profit-and-loss statement itself, and it never files a return with the tax authorities on your behalf. If you work with an accountant using one of the nine connected accounting platforms, your records flow through automatically — read more about those integrations in our overview of accounting software for freelancers. If you work without an accountant, you use the prepared overviews as the basis for your own return.

A question that comes up regularly: can slimzaak also be used as accounting software for associations? The honest answer is that slimzaak wasn't built specifically for that. The tool is primarily designed for freelancers, webshops and marketplace sellers — its features are geared toward invoices, receipts, inventory and VAT returns for businesses, not the typical needs of an association.

If you're specifically looking for bookkeeping for associations, you'll find slimzaak is missing features that are usually essential for that: membership administration, dues collection, and the separate reporting an association owes its members and audit committee. There are free accounting programs built specifically for associations, and for most associations that's the more logical choice.

That said, if your association needs little more than the occasional invoice and a few expenses tracked — for a sponsor, a grant application, or renting out a space, for example — the simplicity of slimzaak's invoicing and expense tracking can still be useful, even though it's not built as full association accounting. If you're unsure, start with the free plan and see whether the basic features cover what your association needs.