Accounting and invoicing for heat pump installers
Planning, grant application, delivery, installation and commissioning: heat pumps are large jobs with many parties and long lead times. Saldiqo issues stage invoices at order, delivery and commissioning, bills grant and own contribution separately and records manufacturers’ invoices.
What comes up for heat pump installers
Large jobs with long lead times
The heat pump arrives weeks after the order. The firm advances the manufacturer’s price before the customer pays.
Grant and own contribution
Customers apply for grants, and the invoice has to show components so that the application is possible.
Servicing afterwards
Maintenance contracts secure recurring income when they are billed on time.
How Saldiqo helps
- Stage invoices at order, delivery, commissioningQuote, stage invoices, final invoice.
- Lines for the grant applicationUnit, installation and ancillary work as separate lines.
- Manufacturer invoices per projectRecord invoices and assign them to the job’s cost centre.
- Servicing as a recurring invoiceSaldiqo creates yearly servicing on schedule.
Typical invoice lines
Examples that often appear on invoices in this industry. You set the prices yourself.
- Air-to-water heat pump, supply
- Installation and hydraulic balancing
- Commissioning and briefing
- Buffer tank and accessories as per delivery note
- Removal of the old system, disposal
- Stage invoice 40 % on ordering the unit
Tax and invoicing in Germany
What applies to invoices in Germany, in short. As of October 2026.
- VAT
- Standard rate 19 %, reduced rate 7 %. Which rate applies to which supply depends on the case. Saldiqo calculates each invoice line with the rate you pick.
- Small business scheme
- Under section 19 of the VAT Act (UStG) you charge no VAT as long as your turnover was at most €25,000 last year and is at most €100,000 this year. Saldiqo shows how much room is left and adds the note to your invoice.
- Mandatory details
- Under section 14 UStG every invoice shows a tax number or VAT ID, a consecutive invoice number, the date of supply and the recipient. Saldiqo checks this before you finalise an invoice. Small invoices up to €250 gross need fewer details.
- E-invoicing
- All businesses have had to be able to receive e-invoices since 1 January 2025. Issuing becomes mandatory from 2027 if last year’s turnover was above €800,000, and from 2028 for domestic business-to-business sales in all cases. Small businesses under section 19 are exempt. Saldiqo creates XRechnung and ZUGFeRD.
- VAT return
- The advance VAT return goes to the tax office through ELSTER, by the 10th after the end of the period. You file monthly if last year’s VAT was above €9,000 and quarterly above €2,000. Saldiqo provides the figures; you file in ELSTER or through your tax adviser.
- Record keeping
- Keep invoices and accounting vouchers for 8 years, books for 10 years and business letters for 6 years. The period starts at the end of the calendar year.
- Late payment
- In the second half of 2026 the default interest rate is 10.52 % between businesses and 6.52 % towards consumers, plus a €40 flat fee that applies to businesses only. Saldiqo has reminder levels with deadlines and fees.
- Getting paid
- Every invoice carries a GiroCode (EPC QR) that customers scan with their banking app. You match payments by uploading the bank statement as CSV or CAMT.
- Tax adviser
- Cash-basis profit calculation (EÜR), a DATEV export and a separate login for your tax adviser are built in.
Frequently asked questions
How do I bill units with a long lead time?
With a stage invoice on order. More stages at delivery and commissioning, and the final invoice deducts them all.
Can I show lines for grant applications separately?
Yes. Unit, installation and ancillary services as separate lines. What details an application requires you clear with the funding body.
Do heat pump installers in Germany have to charge VAT?
Yes, unless they qualify as small businesses under section 19 UStG. That applies when turnover was at most €25,000 last year and is at most €100,000 this year. The limit is hard: VAT is due on the sale that takes you over it.
Do heat pump installers in Germany need e-invoicing?
Every business must be able to receive e-invoices since 2025. Issuing is mandatory from 2027 if last year’s turnover was above €800,000, and from 2028 for domestic business-to-business sales in general. Small businesses, invoices up to €250 and tickets are exempt. Private customers still get a normal invoice.
How long do heat pump installers have to keep invoices?
Invoices and vouchers for 8 years, books for 10 years and business letters for 6 years, counted from the end of the calendar year. You can store receipts digitally in Saldiqo. The legal duty to keep records and to document your procedures stays with you.
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As of October 2026. General information, not legal or tax advice, without guarantee. For your case ask your tax adviser.