Invoice for Freelancers 2026 — data, VAT, and legal requirements

If you're a freelancer in Spain, every mobile phone invoice you receive can become a tax deduction — but only if it meets the legal requirements of the Invoicing Regulation (Royal Decree 1619/2012). An incomplete or incorrect invoice exposes you to rejection in tax authority inspections and loss of VAT deductions you actually paid. In this guide, we explain what an invoice for freelancers must contain in 2026, what errors to avoid, and how to verify that your eSIM providers comply with Spanish regulations.

What is a valid invoice for freelancers in Spain

A valid invoice is a document that justifies a purchase and allows you to deduct the expense in personal income tax (IRPF) and recover VAT paid in your quarterly declaration. For the tax authority to accept it, it must comply with Articles 6 and 7 of the Invoicing Regulation: complete issuer data, complete recipient data, service description, taxable base, VAT rate applied, VAT amount, total, and sequential invoice number.

Simplified invoices (receipts with minimal data) are only valid up to €400, and they don't qualify for VAT recovery. If your data plan costs more than €400 per year, or if you make multiple payments totaling more than that amount with the same provider, you need a complete invoice.

At eSIM Ahora we issue a complete invoice automatically with every purchase, including all mandatory fields — customer VAT number, issuer business name (eSIM Ahora S.L.), issuer tax ID, fiscal address, and VAT itemized at 21%. You don't need to request it separately: it appears in your confirmation email and in your customer dashboard.

Mandatory issuer data

Every provider must include:

• Complete business name — the trade name alone is not sufficient. Example: "eSIM Ahora S.L.", not just "eSIM Ahora".
• Tax ID/VAT number of the issuer — the company's tax identification number. Foreign platforms registered in the EU must show their VAT ID.
• Complete fiscal address — street, number, postal code, city, and country.
• Contact information — email or customer service phone.

If you receive an invoice without a business name or without a tax ID, request a corrected version. The tax authority may reject the VAT deduction if any of these fields are missing.

Mandatory recipient data (you, the freelancer)

The invoice must include:

• Your full name or business name — if you invoice as an individual, your first and last name; if you have a company, the business name.
• Your tax ID/VAT number — essential so the tax authority associates the invoice with your economic activity.
• Fiscal address — the one you have registered on your tax forms (models 036/037).

Some international eSIM providers (Airalo, Holafly, Saily) issue invoices without a field for the customer's tax ID, or only with an optional "Tax ID" field that doesn't always print on the PDF. If you buy from one of those providers, save the payment receipt and confirmation email — in an inspection you'll have to justify the expense with supporting documents.

We request the tax ID at checkout and print it on the invoice, because we know most of our Spanish customers are freelancers or small businesses who need to justify every euro.

Service or product description

The invoice must describe what you purchased with sufficient detail:

• ❌ "Data service" (too generic)
• ✅ "eSIM 3 GB for Spain — 30 days validity"
• ✅ "Data plan 10 GB Europe region — activation within 24 hours"

The description helps the tax authority verify that the expense is related to your activity. If you travel for work and buy an eSIM for Mexico or Argentina, the invoice should mention the destination — this makes it clear the expense is professional.

VAT itemization: taxable base, rate, and amount

This is the most critical section for recovering VAT. The invoice must show:

• Taxable base — the price without VAT.
• VAT rate — in Spain, telecommunications services are taxed at 21% (standard rate).
• VAT amount — the quantity of VAT you paid.
• Total with VAT — base plus VAT amount.

Example:

If the invoice only shows the total (€14.52) without itemizing the base and amount, you won't be able to deduct the VAT on your quarterly form. You'll have to ask the provider for a corrected invoice with the proper itemization.

Invoice number and issue date

Each invoice must have:

• Unique and sequential invoice number — example: "2026/0452". Numbers cannot repeat or be skipped.
• Issue date — the day the invoice was issued. It can match the purchase date or be issued later (up to 30 days after VAT accrual).

The numerical series must be sequential within the fiscal year. If in January you receive invoice 2026/0120 and in February invoice 2026/0090, something is off — the provider may be using different series by country or product, which is valid as long as each series is internally sequential.

When to require a complete invoice vs. simplified invoice

Simplified invoices (purchase receipts) are valid for expenses up to €400, but have limitations:

• You cannot deduct the VAT paid.
• They don't include all recipient data.
• The tax authority accepts them as proof of personal income tax expense, but not for VAT purposes.

For any recurring mobile phone purchase (monthly plans, top-ups, eSIMs for Spain or France), it's best to require a complete invoice from the start. This avoids problems in your quarterly VAT declaration.

At eSIM Ahora we issue a complete invoice regardless of amount — even for plans in the $3-$8 range. There's no need to request it: it's generated automatically.

Electronic invoices: validity and retention

Since 2013, electronic invoices have the same legal validity as printed ones, provided they guarantee authenticity of origin, content integrity, and readability. Most eSIM providers send the invoice as a PDF by email — that PDF is valid if it complies with the Invoicing Regulation requirements.

You must retain electronic invoices for 4 years from the transaction date. The tax authority recommends saving them as digitally signed PDFs or with a timestamp, though it's not mandatory for B2C invoices. As a freelancer, it's sufficient to archive the PDFs in a secure folder (local or cloud) and make backups.

What to do if you receive an incorrect invoice

If the invoice from your eSIM provider has errors (missing your tax ID, no VAT itemization, wrong business name), you have two options:

1. Request a corrected invoice — ask the provider to issue a new invoice with the correct data and to void the original. The corrected invoice must reference the original invoice.
2. Request a replacement invoice — if the error is minor (a letter in your name, a digit in your tax ID), some providers issue a replacement without a new series number. But the tax authority prefers the formal correction.

At eSIM Ahora, if you notice an error on your invoice, write to support (email or Telegram) with the order number and correct information. We issue the corrected invoice within 48 hours.

How to deduct mobile phone expenses as a freelancer

Freelancers can deduct 100% of mobile phone expenses if the use is exclusively professional. If you use the same phone for work and personal life, the tax authority typically allows a 50% deduction — though there's no fixed percentage in the law.

To justify a 100% deduction:

• Contract a separate line or eSIM for professional use.
• Keep all invoices with your tax ID.
• Include the expense in the expense log of your business activity.

If you travel for work to Germany, Italy, or Portugal and buy an eSIM to avoid roaming charges, that expense is 100% deductible — provided you can prove the trip was professional (hotel invoice, airline ticket, meeting schedule).

Comparison: what other eSIM providers issue

As of May 2026, major travel eSIM providers had the following invoicing policies for Spanish customers:

Airalo and Saily issue invoices in English without customer tax ID and without VAT itemization per Spanish regulations — you can use them as proof of expense for personal income tax, but not for VAT recovery. Holafly issues a Spanish invoice if you request it at checkout, but if you don't check that box, you receive only a generic receipt.

We, eSIM Ahora, issue a complete invoice with every purchase because we know 60% of our Spanish customers are freelancers or small businesses — and we don't want you to have to request corrected invoices afterward.

FAQ

How long must I keep mobile phone invoices?

You must retain invoices for 4 years from the transaction date. The tax authority can inspect that period and ask you for proof of deducted expenses. Save the PDFs in a secure folder with backups, and organize them by year and quarter for easy retrieval.

Can I deduct 100% of my phone expense if I use it for personal use too?

The tax authority allows 100% deduction only if the use is exclusively professional. If you use the same phone for work and personal life, the safest approach is to deduct 50% — though the law doesn't fix an exact percentage. If you have a separate line for work (for example, a dedicated eSIM for business travel), you can deduct 100% of that line.

What do I do if my eSIM provider doesn't issue invoices with my tax ID?

Request a corrected invoice by email, stating your tax ID and complete fiscal address. If the provider cannot issue Spanish invoices (because it's registered outside the EU or lacks a European VAT ID), keep the payment receipt and confirmation email — the tax authority may accept them as proof of expense, though you won't be able to deduct the VAT paid.

Are invoices from foreign providers valid in Spain?

Yes, as long as they comply with the Invoicing Regulation requirements: issuer data (business name, VAT ID or equivalent), recipient data (your tax ID), service description, taxable base, itemized VAT (if applicable), and total. If the provider is in the EU, it must charge Spanish VAT (21%) to Spanish customers. If outside the EU, it may not charge VAT — in that case, you must self-assess the VAT on your quarterly form (reverse charge mechanism).

Can I use an eSIM invoice from a personal vacation trip?

Only if the trip has a professional component. If you travel for leisure and buy an eSIM to browse at the hotel, that expense is not deductible. If you travel to a conference, trade show, or business meeting and buy an eSIM for Japan or Thailand, the expense is deductible as a business travel cost — but keep documentation proving the professional nature of the trip (conference registration, meeting schedule, hotel invoice).