Home Small Business & Retail All Details

Everything you need to know about invoicing in small business and retail.

And how we take the work off your hands.

1. Mandatory details – what belongs on every invoice?

You sell a pallet of paint to a painting contractor. Or you rent out 10 kiteboards for the weekend. No matter what – as soon as you write an invoice, fixed rules apply. If something is missing, your business customer cannot claim input tax deduction.

Common mistakes:

  • Invoice number missing or not sequential
  • Tax number / VAT ID not provided
  • Service description too vague ("Various goods")
  • Date of service/delivery missing
  • Wrong tax rate (7% vs. 19%)

Legal situation – §14 UStG

  • Name & address of supplier and customer
  • Tax number / VAT ID
  • Invoice date and sequential invoice number
  • Quantity & type of delivery/service – specific, not "goods"
  • Date of service or service period
  • Net amount + tax rate + tax amount – separated for mixed tax rates
  • Small amount invoices (up to €250 gross): Simplified requirements per §33 UStDV

How RuckZuckRechnung helps you:

  • Automatic mandatory details check – if something is missing, you're notified immediately
  • Separate tax rates – items with 7% and 19% are automatically split
  • Sequential invoice numbers – gapless and traceable
  • Item management – save your most common products and rental items, next time just one click
Bottom line: No invoice leaves RuckZuckRechnung without all mandatory details. Whether paint, kiteboards or tool rental.

2. B2B and B2C – the difference in invoicing

Your shop has two worlds: In the morning, the painting contractor comes and buys on account. In the afternoon, the hobby painter is at the register. In the evening, a corporate client calls wanting to rent equipment for their team event.

  • B2B: Full invoice with all §14 mandatory details – your customer needs it for input tax deduction
  • B2C: Receipt or simplified invoice is often enough – but rules still apply
  • Mixed cases: A club orders equipment – is that B2B or B2C?

Legal situation

  • §14 para. 2 UStG: Invoicing obligation within 6 months to entrepreneurs
  • B2B: All mandatory details required, customer needs input tax deduction
  • B2C: Simplified small amount invoice up to €250 (§33 UStDV)
  • Rental tip: Short-term rental is also taxable – invoice mandatory for B2B

How RuckZuckRechnung helps you:

  • Select customer type – business or private customer, invoice adapts automatically
  • Complete B2B invoices – all mandatory details automatically
  • Simplified receipts – for small amount invoices only the necessary details
  • Customer database – set up once, everything is there next time
Bottom line: Business or private customer? One click – and the invoice is correct.

3. E-invoicing & ZUGFeRD – the new obligation

Your major client suddenly demands an "e-invoice"? That's not a PDF via email – it's a machine-readable format. From 2028, e-invoicing becomes mandatory for all B2B transactions.

Deadlines & obligations

  • Since 01.01.2025: You must be able to receive e-invoices
  • Until 31.12.2026: PDF sending still allowed with recipient's consent
  • 2027 (revenue ≤ €800,000): PDF with consent still allowed
  • From 01.01.2028: Only structured e-invoices to business customers

What is ZUGFeRD? A PDF invoice with embedded XML data. Your customer sees a normal invoice – their accounting software reads the data automatically.
Important: The e-invoicing obligation only applies to B2B. Invoices to private individuals are not affected.

How RuckZuckRechnung helps you:

  • ZUGFeRD automatic – every invoice is a ZUGFeRD-compliant e-invoice, no extra effort
  • Future-proof – you're already ready for 2028 today
  • Compatible – SAP, DATEV, Lexware? The ZUGFeRD invoice is read without problems
Bottom line: E-invoicing? Already included. From day one.

4. Small business exemption – §19 UStG done right

Just opened a small shop? Started a rental business on the side? Then you might be using the small business exemption. The most common mistake: showing VAT on the invoice even though you're a small business. Consequence: You owe the VAT to the tax office (§14c UStG).

§19 UStG – Requirements

  • Revenue in previous year ≤ €25,000 (raised since 2025)
  • Revenue in current year expected ≤ €100,000
  • No VAT shown – no tax rate, no tax amount
  • Mandatory note: "Pursuant to §19 UStG, no VAT is charged."
  • All other mandatory details (§14 UStG) still apply
  • Retail: Distinction between 7%/19% no longer applies – you don't show any VAT

How RuckZuckRechnung helps you:

  • Small business mode – activate once, all invoices without VAT
  • Automatic notice text – the §19 notice appears on every invoice
  • No accidental VAT display – the tax rate isn't even shown
Bottom line: Small business? One switch – and you can't go wrong.

5. Deposits, rental receipts & billing correctly

You rent out kiteboards, bicycles, tools or event equipment? Then you know the questions: How do I account for the deposit? Does the rental receipt need to be a full invoice? How do I bill for damages or late returns?

Deposits & rental receipts

  • Deposits are not revenue – as long as they are refunded
  • Deposit is not shown as a VAT item on the invoice
  • If the deposit is retained (damage), the amount becomes a taxable service
  • Rental receipts must be full invoices for B2B or over €250
  • Service period is mandatory (§14 para. 4 no. 6 UStG) – for daily rental: date, for weekly rental: "from – to"

How RuckZuckRechnung helps you:

  • Flexible line items – daily rental, weekly rental, accessories and insurance as separate items
  • Service period – directly on the invoice, mandatory detail fulfilled
  • Item management – save equipment as master data, next rental just one click
  • Professional receipts – your rental receipt looks just as professional as a sales invoice
Bottom line: 3 kiteboards, 2 wetsuits, period Saturday to Monday? Everything on one clean invoice – in 2 minutes.

6. Record retention – §14b UStG & GoBD

Every invoice you issue must be stored for 10 years. Whether selling a can of paint or renting out an excavator. Digital invoices must be archived digitally – GoBD-compliant.

Your obligations

  • 10 years retention obligation (§14b para. 1 UStG)
  • Digital invoices must be archived digitally (printout is not enough!)
  • GoBD: Traceability, immutability, completeness, timeliness, order
  • Every invoice in original format – no subsequent changes
  • Systematic filing with search function for tax audits

How RuckZuckRechnung helps you:

  • Automatic archive – all invoices stored, 10 years, accessible at any time
  • GoBD-compliant – immutable storage, complete documentation
  • Searchable – find any invoice by customer, date, amount or number
  • German servers – your data stays in Germany, GDPR-compliant
Bottom line: 10 years of retention? Runs automatically. You sell – we archive.

7. Late payment & dunning – get paid faster

Especially in B2B business, small business owners and retailers know the problem: The painting contractor picked up the paint 6 weeks ago – the invoice is still outstanding. Dunning feels uncomfortable, but unpaid invoices burden your cash flow.

Legal basis

  • §286 BGB: Your customer automatically goes into default 30 days after the due date
  • §288 BGB: Default interest: 5% above base rate (private) or 9% (business customers)
  • §288 para. 5 BGB: For B2B additionally €40 dunning flat rate
  • Tip: Clear payment terms (e.g. 14 days) and early payment discount (2% within 7 days) accelerate payment

How RuckZuckRechnung helps you:

  • Payment status at a glance – open, overdue or paid, instantly visible
  • Automatic payment reminders – politely worded, by email
  • Due date – clearly shown on every invoice
  • Dunning levels – from friendly reminder to formal dunning notice, automatically escalating
Bottom line: Outstanding invoices? We remind your customers – politely but firmly.

8. Professional appearance – your business, your brand

Your invoice is your business card. When a major client receives an invoice from Word or Excel – without a logo, with misaligned formatting – it doesn't leave a good impression. Especially in the rental business, you can stand out immediately with professional invoices.

And if you also serve tourists – at the lake, at the beach, in holiday regions – then a multilingual invoice is worth its weight in gold.

Professional standards

  • Consistent appearance strengthens your customers' trust
  • Logo and company colors on every invoice
  • Multilingual support is a competitive advantage with international clientele
  • Fast invoicing signals professionalism

How RuckZuckRechnung helps you:

  • Professional templates – consistent design with your logo, your colors
  • Multilingual – German, English, Polish, Turkish, Ukrainian and Russian
  • Consistent appearance – whether €15 bike rental or €5,000 construction equipment rental
  • Quickly created – in under 5 minutes, even between two customers at the counter
Bottom line: Your invoice says more about your business than you think. Make it your best calling card.
At a glance

What's inside RuckZuckRechnung – for small business owners and retailers

What concerns you What RuckZuckRechnung does
Forgetting mandatory details Automatic check of all §14 details
B2B vs. B2C confusion Select customer type – invoice adapts
E-invoicing obligation from 2028 ZUGFeRD already in every invoice today
Small business exemption §19 mode – one switch, done
Deposits & rental receipts Flexible items, periods, accessories
Store invoices for 10 years GoBD-compliant digital archive
Customers pay too late Automatic payment reminders
Invoice looks unprofessional Professional templates with branding

Try it out – free and without obligation.

Create your first invoice in under 5 minutes. All mandatory details and ZUGFeRD included.

Try it free now Back to Small Business & Retail overview