Late Payment Interest for Tradespeople: How to Charge It

When a customer does not pay, you can charge late payment interest, and in Sweden the rate is set by law rather than by you. Under räntelagen (1975:635) the statutory rate is the Riksbank's referensränta plus 8 percentage points. The clock starts on the due date if a due date was agreed in advance; if it was not, it starts 30 days after you sent the invoice. On top of the interest you can add a 60 kr reminder fee (only if that fee was agreed before the debt arose), 180 kr for a formal collection demand, and — for business customers only — a fixed 450 kr förseningsersättning. Consumers are protected by a hard 30-day floor you cannot shorten. Everything below is the detail: how to work the number out, what changes between a consumer and a company, and the wording that makes the claim stick.

The number in your invoice template is probably wrong

Most trades firms typed a percentage into their invoice footer once, years ago, and never touched it again. That was survivable when the reference rate sat at zero for a decade. It is not survivable now.

The referensränta is not a fixed number. The Riksbank sets it twice a year, on 1 January and 1 July, based on the policy rate at the end of the preceding month, rounded to the nearest half percentage point. It has moved repeatedly through the last rate cycle, so a hardcoded figure has been wrong on at least one side of it.

The fix is to stop writing a number and start writing the formula. Look up the current referensränta at riksbank.se and diary two reminders a year.

How late payment interest for tradespeople is calculated

Section 6 of räntelagen gives one formula:

Referensränta + 8 percentage points = annual late payment interest.

Three things people get wrong:

• It is an annual rate, charged per day. The convention is actual days divided by 365. It is not 10% per month, and it is not 10% flat on the invoice.
• You calculate on the gross amount, VAT included. The customer owes the whole invoiced sum, so interest runs on the whole invoiced sum.
• The rate follows the calendar, not the invoice. If the debt runs across a 1 January or 1 July reset, you split the calculation and use each period's rate for the days in that period.

Worked example. An unpaid invoice of 24 000 kr including VAT, 45 days late, in a period where the referensränta is 2.00% (so the rate is 10.00%):

24 000 × 0.10 × 45 / 365 = 295.89 kr

That is small, which is the honest point almost nobody makes: the interest is not the lever. It is the paper trail that lets you escalate without looking arbitrary. The fees and the escalation are what move money.

Late payment interest is also outside VAT. Do not add moms to it, and do not book it as turnover on the job.

When the clock actually starts

If you agreed a due date in advance

Interest runs from the day after the due date. "Agreed in advance" means the terms existed before the debt did — in the quote the customer accepted, in a service agreement, or in terms they signed up to. This is section 3 of räntelagen.

If you did not agree a due date

Interest runs 30 days after you sent the invoice or a written demand for payment, and only if that document told the customer interest would be charged. This is section 4. The 30 days is the default in every job where nobody discussed payment terms, which is most jobs.

The consumer floor

Against a private customer you cannot get inside 30 days by printing "payment terms 10 days" on the invoice. A consumer does not owe late payment interest for the period before 30 days have passed since the invoice was sent, even where a shorter due date was set. You can still ask for payment in 10 days. You just cannot start the interest early. A term genuinely agreed with the consumer in advance is a different matter, but a number printed on an invoice after the work is not an agreement.

The fees you can add — and the one everyone gets wrong

These come from lagen (1981:739) om ersättning för inkassokostnader and its ordinance. The amounts have been stable for a long time, but confirm the current figures at kronofogden.se before you print them.

Two traps:

• The reminder fee needs a prior agreement. This is the single most-charged illegal fee in the trades. If the 60 kr was never agreed before the job, you are not entitled to it. Put it in the quote, not the invoice footer.
• The 450 kr absorbs the small fees. Against a business customer, reminder and collection fees are only recoverable to the extent they exceed the 450 kr. You do not stack 450 + 60 + 180.

Consumer versus company: what actually differs

That last row matters more than the rate does. A consumer debt goes stale in three years unless you interrupt it with a written demand. Invoices quietly dying in a drawer is a bigger loss than any interest you failed to charge.

The exact wording to put on the invoice

Put this on the quote first, because that is what makes it an agreement. Then repeat it on the invoice.

Betalningsvillkor: 30 dagar netto. Vid för sen betalning debiteras dröjsmålsränta enligt räntelagen, referensränta + 8 procentenheter, från förfallodagen till dess betalning sker. Påminnelseavgift 60 kr samt lagstadgad inkassoavgift tillkommer. Vid betalning från näringsidkare tillkommer förseningsersättning med 450 kr enligt lagen om ersättning för inkassokostnader.

In English, for an English-speaking customer in Sweden:

Payment terms: 30 days net. Overdue amounts carry statutory late payment interest under the Swedish Interest Act (räntelagen) at the Riksbank reference rate plus 8 percentage points, from the due date until payment is received. A reminder fee of 60 kr and the statutory collection fee will be added. Business customers are additionally charged 450 kr fixed late compensation.

Note what the wording does not do: it does not state a percentage. It states the formula. That is the whole point — the clause stays correct through every rate reset without you editing a template.

What to do when they still do not pay

The ladder, in order, with no drama:

1. Day 31: reminder. Written, dated, with the outstanding amount, the interest accrued so far, and the 60 kr fee if it was agreed. Send it by email and keep the sent copy.
2. Day 45: pick up the phone. Half of late invoices are a lost invoice, a wrong reference, or a customer who is unhappy about something and did not say so. Ten minutes here beats three letters.
3. Day 60: inkassokrav. A formal collection demand with a payment deadline of at least eight days and a clear statement of what happens next. This is the point where 180 kr becomes chargeable.
4. Day 75: betalningsföreläggande at Kronofogden. A 300 kr application fee, plus roughly 380 kr you can claim for your own work on it. If the customer does not object, you get an enforceable decision without a court.
5. Disputed? If they object on the substance, it goes to court and it is time to talk to someone qualified. Interest keeps running throughout.

Firms skip this ladder because reconstructing the invoice date, the sent date and the accrued interest takes an hour of digging per job. In OdinTask the payment terms live on the quote the customer signs, the invoice inherits them, the send date is timestamped, and the invoice syncs to Fortnox or Visma, so "when did we send it and what is owed today" is on the screen rather than in your memory.

If you are not in Sweden

The structure is broadly the same across Europe because it comes from the EU late payment directive; the labels differ.

• UK: the Late Payment of Commercial Debts (Interest) Act 1998 gives Bank of England base rate plus 8% — the same plus-8 shape — with a default 30 days, but it is business-to-business only. Fixed compensation is £40, £70 or £100 depending on debt size, plus reasonable recovery costs. Against a domestic customer you are relying on your contract terms.
• Ireland and most of the EU: reference rate plus 8, 30-day default, €40 fixed compensation, B2B only.
• New Zealand and Australia: no general statutory late payment interest for private debts. If it is not in the contract you signed before the job, you have no rate. Write it into your terms.

The universal lesson is the same one Sweden codified: the entitlement is created before the work starts, not after the invoice goes unpaid.

Five mistakes that kill the claim

• Charging a reminder fee that was never agreed in advance.
• Charging 450 kr to a private customer. That is a consumer-law problem, not a rounding error.
• Charging a monthly percentage. "2% per month" is 24% a year and against a consumer it will not survive scrutiny.
• Treating the invoice footer as a contract. It is evidence of what you asked for, not of what was agreed.
• Letting a consumer debt run past three years. The rate stops mattering when the claim is gone.

Fix the formula in your template, move the terms onto your quote, and put two dates in the diary: 1 January and 1 July. That is the whole job. If you want the terms, the send dates and the running total handled by the system instead of by your memory, start a free trial and see the pricing page.