Voluntariness of both parties

If a sole trader is not required to issue e-invoice, must the customer company receive the invoice as e-invoice?

Short answer

If a sole trader has no statutory obligation to issue e-invoice, for example because the trader is not a VAT payer registered under § 4, § 4b or § 4c, and invoices a company in another, non-electronic form, the company is not required to receive that particular document as e-invoice because it is not an e-invoice in the first place. The company’s receiving obligation applies when a supplier that is required to issue e-invoice actually sends one. The parties may nevertheless agree voluntarily to exchange e-invoices even where the law does not require it.

Self-employed person with no obligation to issue e-invoices

Invoice in a different form

If he is not a VAT payer according to Section 4, Section 4b, Section 4c.

s.r.o. does not accept e-invoice

Because it's not about her

A document that is not an e-invoice cannot be accepted as such.

Voluntary agreement

Maybe even out of duty

Both parties can opt for e-invoice voluntarily.

General readiness

Not forcing a form

The obligation to accept refers to invoices that are actually e-invoices.

Detailed explanation

The obligation of a legal entity (in this case, a limited liability company) to be capable of receiving e-invoices is a general technical requirement, not an obligation to insist on the electronic format from every individual supplier. If a self-employed person has correctly assessed their VAT and e-invoice obligations and is not required to issue an e-invoice, they may continue to invoice in the current format. However, if both parties decide that they wish to take advantage of the benefits of the structured format even where the law does not require it, they may agree to do so voluntarily — as we have already established, the voluntary participation of entities without a legal obligation (such as non-VAT payers) in the e-invoicing system is expressly permitted.

As set out in the Act

The scope of entities obliged to issue electronic invoices is defined in Section 85o(2) of Act No. 222/2004 Coll. on VAT, as amended by Act No. 385/2025 Coll. The possibility of voluntary participation in the electronic invoicing system by entities not subject to a legal obligation is confirmed by the official methodological and information materials of the Slovak Financial Administration concerning e-invoice.

Practical examples

A self-employed person not registered for VAT sends a standard invoice to a limited liability company (s.r.o.) by email in PDF format — the s.r.o. accepts it in this form without breaching the law.
The self-employed person and the limited liability company agree that they wish to communicate using e-invoices on a voluntary basis, even though the law does not require this in their case.
The limited liability company has a digital mailbox set up in case any other supplier, who is obliged to do so, sends it an e-invoice.

Most common mistakes

“The limited liability company must require e-invoices exclusively from every supplier.” If a supplier is not obliged to issue an e-invoice, the limited liability company will accept the invoice in the form in which it was issued.
“Voluntary e-invoicing outside the B2B obligation is not possible.” Both parties may voluntarily agree to exchange e-invoices even outside situations required by law.
“If a limited liability company is not required to accept e-invoices from a self-employed person, it does not need to have a digital mailbox at all.” As a legal entity, it has a general obligation to be prepared to receive e-invoices from those suppliers who are required to issue them.

Conclusion

s.r.o. cannot force an e-invoice from a supplier who does not have to issue it; however, both parties can agree on the voluntary exchange of e-invoices outside of the relationship required by law.

Legal basis

Act No. 222/2004 Coll. on VAT, Section 85o(2) (as amended by Act No. 385/2025 Coll.)
Official methodological and information materials Financial Administration of the Slovak Republic k e-invoice