Common mistakes in your first year as a freelancer
Written by Ilias Aarrass7 min read · Published on · Last reviewed on 
In short
The costliest beginner mistake is not reserving for tax: at a modest profit, set aside 20 to 25 per cent of every paid invoice, plus the VAT you charged.
- Without 1,225 demonstrable hours the self-employed deduction lapses; in 2026 it is 1,200 euros.
- You must keep your records for seven years, so scan receipts on the spot.
- An error in a VAT return is corrected with a supplementary return up to five years back.
- One fixed weekly admin slot prevents almost all seven mistakes at once.
Your first year as a freelancer is an instructive year, but also a year in which mistakes are easily made. Some of them can cost you money. By knowing them in advance, you prevent a lot of hassle. This article lists the most common mistakes.
Not reserving money for tax
The most common mistake is seeing your entire turnover as income and setting nothing aside for tax. At the end of the year an assessment follows that you can't pay. So from the first euro, set aside part of your income for income tax and VAT.
Messy bookkeeping
Many starters let their bookkeeping slide and have to sort everything out at the end of the year. That costs time and leads to errors and missed deductions. Keep your records tidy from day one, preferably with bookkeeping software.
Losing receipts and invoices
Without proof of your costs you can't deduct them or reclaim the VAT. Yet many starters lose receipts. Make it a habit to store every receipt digitally right away. You're also obliged to keep your records for seven years.
Missing deductions
Starters often leave money on the table by missing deductions, such as the starter's deduction, the investment deduction or start-up costs. Look into what you're entitled to, or get advice. A good bookkeeper often pays for themselves by still using missed benefits.
The seven mistakes at a glance
Every first year holds the same traps. These are the seven we meet most in practice, with the damage and the fix.
- Not reserving for tax. The assessment arrives after a year, when the money is gone. Set a share aside per invoice immediately; see how much to set aside.
- Private and business mixed in one account. A separate account from day one saves hundreds of search hours; see keeping private and business separate.
- Keeping receipts for later. Thermal receipts fade and later never comes. Scan on the spot.
- No time log. Without 1,225 demonstrable hours the self-employed deduction lapses, and reconstruction fails.
- Quoting too cheaply. Setting a rate without calculating subsidises your clients; see setting your rate.
- Underestimating VAT filing: missing the deadline, forgetting the nil return, leaving input VAT unclaimed.
- Waiting too long to ask for help. Engaging a bookkeeper once a backlog and an assessment exist is the expensive order.
The seven mistakes and what they cost
These are the slips that most often occur in a first year, with what you concretely do to avoid them.
| Mistake | What it costs | What to do |
|---|---|---|
| Not setting money aside for tax | An assessment you cannot pay | Put 20 to 30 percent of every paid invoice aside |
| Spending the VAT you received | A shortfall at every quarterly return | VAT belongs in the reserve account, not your turnover |
| Losing receipts | No VAT deduction and no cost deduction | Scan them immediately with your phone |
| Not logging hours | The self-employed and starter's deductions | Five minutes a day, not a reconstruction afterwards |
| Missing deductions | Hundreds of euros a year | Run through the checklist once a year |
| Mixing private and business | Hours of sorting out and trouble in an audit | A separate account from day one |
| Invoicing late or not at all | A hole in your cash flow | Invoice weekly at a fixed moment |
Frequently asked questions
What is the costliest beginner's mistake?
Not reserving for tax. The first assessments arrive late and then stack: income tax, healthcare contribution and sometimes a provisional assessment for the new year at once.
How much should I set aside in my first year?
At modest profit, 20 to 25 per cent of every paid invoice, plus the VAT separately. Better too much than too little; the surplus becomes a windfall at assessment time.
Do I need a bookkeeper from day one?
Not necessarily, but you do need a system: separate account, software, a weekly quarter-hour. One advisory call at the start prevents most structural errors and costs little.
I forgot to track my hours. Now what?
Reconstruct as well as possible from diary, email and invoices, and start real logging today. For next year the running log is what holds up.
Can errors in my first returns still be fixed?
Yes. VAT is corrected with a supplementary return up to five years back, income tax by refiling or an official reduction. The sooner, the cheaper.
Which mistake do starters underestimate most?
The time log. It feels like bureaucracy, but the self-employed deduction and your credibility in an audit hang on it. Five minutes a week suffices.
Sources
- Self-employed deduction 2026Belastingdienst · belastingdienst.nl
- Keeping records: 7 and 10 yearsBelastingdienst · belastingdienst.nl
Sources checked on
This article provides general information based on the rules known for 2026 and does not replace personal tax advice. For your specific situation, we're happy to take a look with you.
