Cairos as an alternative to Billin
Billin is one of the simplest and cheapest invoicing programs on the Spanish market, and at the entry end it is hard to beat on price. Here are its prices, checked and dated, what it does better and where Cairos fits.
What each one costs
Billin publishes both prices, the annual one and the monthly one, and in both cases states that VAT goes on top. Cairos's are excluding VAT too, so the comparison is clean.
| Billin plan | Per month, paid annually | Per month, paid monthly | Clients | Users |
|---|---|---|---|---|
| Basic | 6,60 € | 8,00 € | From 0 to 5 | 1 |
| Pro | 14,00 € | 17,00 € | From 6 to 50 | 3 |
| Unlimited | 23,00 € | 28,00 € | Unlimited | Unlimited |
Taken from billin.net/precios on 25 August 2026. The prices are shown with the tag «+IVA» — VAT on top. The plans also cap products (10, 50 and unlimited) and document digitisation (5, 50 and 250 a month), and invoices are unlimited on all three. The way in is a 30-day trial: that page showed no permanent free plan.
And what Cairos costs
| Cairos plan | per month | What they give you and where they limit you |
|---|---|---|
| Free | 0 € | 30 documents a year · 1 user · 1 company |
| Cuarzo | 10 € | 500 documents a year · 2 users · 1 company |
| Ámbar | 25 € | 1,500 documents a year · 5 users · 1 company |
| Jade | 50 € | 5,000 documents a year · 10 users · up to 3 companies |
| Zafiro | 100 € | 20,000 documents a year · 25 users · 5 companies · 150 GB |
| Rubí | 175 € | 60,000 documents a year · 60 users · 15 companies · 400 GB |
| Diamante | 275 € | Documents, users and companies with no limit · 1 TB |
Prices are per company and exclude VAT, the same ones on the pricing page. The column shows the month-by-month price; paid annually they work out at €8, €20, €40 and €80 a month. The free plan does not expire and asks for no card: it is not a trial, it is a plan.
These prices go out of date
The prices in the table are the list prices published on 25 August 2026, without promotions and excluding VAT. A program can change them tomorrow, and welcome promotions change almost every month. Before you decide, go to their website and look for yourself. If you see anything out of date on this page, write to us at hola@cairos.es and we will correct it.
What Billin is better at
The third of these cards may cost us a sign-up, and it goes here anyway: it is the fact that decides a migration more than any other.
The longest trial of the three
Thirty days with every feature, according to their site. That is double Holded's 14 days and Quipu's 15, and for an autónomo who wants to try out one short quarter it is a real advantage.
Unlimited invoices from the cheapest plan
Their Básico plan, at €6.60 a month paid annually, does not cap the number of invoices: it caps clients, up to 5, and products, up to 10. Our free plan does have a ceiling: 30 documents a year.
TicketBAI and Facturae advertised
Their website says, literally, that it issues unlimited Verifactu, Facturae and TicketBAI electronic invoices. If you invoice from Álava, Bizkaia or Gipuzkoa your rule is TicketBAI and not VeriFactu; if you invoice the public sector, you need Facturae. Ask us about your case before you switch.
What Cairos fits best
The big difference is not the price of the invoice: it is what happens when the quarter comes round and has to be closed.
Zero euros, for ever
With VeriFactu, a chained record and a QR code from the very first invoice, no card and no countdown. Below 30 documents a year, you pay nothing.
Taxes and books from €8
Eight euros a month paid annually, ten month by month. Expenses and input VAT, forms 303, 390, 347, 349, 111, 115, 130 and 180 worked out with their breakdown, and the VAT record book and the general journal kept up to date.
Modules a generalist does not bring
A members' register and fees with a SEPA direct debit batch, donations and modelo 182, cooperative surplus, VAT-exempt club fees, grants, recargo de equivalencia, IGIC, IPSI and modelo 720.
The modules almost nobody else brings
They switch on when you say in the settings what kind of entity you are, and none of them is charged separately, although not all of them are in the first paid plan: ask us about your case. Inside the ERP this block is marked as beta, which is what it is.
Members, fees and SEPA direct debit batches
A members' register with joiners, leavers and dates, recurring fees and their collection by direct debit, with a file for the bank and control of returned debits.
Donations and modelo 182
One-off and regular donors, certificates with the deduction each one is entitled to — recurrence worked out on its own — and the annual informative return.
Membership card with a QR code
It is scanned at the door and answers yes or no on the spot. Six designs, card size or eight to an A4 sheet, and suspension for non-payment without reprinting anything.
Cooperative surplus
The mandatory reserve fund, the education and promotion fund and the cooperative refund, with the percentages from whichever cooperatives act applies to you.
VAT-exempt club fees
What carries VAT and what does not in a sports club: membership fees, the school, the bar, sponsorship and ticket sales, each one on its own.
Grants with their evidence
What was awarded, what has been received in instalments and what spend is still to be evidenced before the deadline runs out. From the Cuarzo plan onwards.
Grants, volunteering and accounts
What is handed to beneficiaries recorded in its own grant accounts rather than as a purchase, volunteers with their insurance, and the draft accounts under the chart of accounts for non-profit organisations.
Recargo, IGIC, IPSI and modelo 720
Recargo de equivalencia for retailers, the Canary Islands' IGIC, the IPSI of Ceuta and Melilla, and the informative return on assets held abroad.
Cairos is new and small
We do not have the track record of a program with years on the market, or a network of integrations, and there are concrete things others advertise and we do not: TicketBAI and Facturae are the best example. If your rules are the foral ones, or you invoice the public sector, ask us before you move anything. We would rather lose a sign-up than leave you halfway.
Issue the same five invoices in both
And keep the one that made you think less. Our free account does not expire.
Questions about this comparison
For invoicing and little else, Billin is hard to beat
The difference shows up the day you have to close the quarter or run an association.
Prices checked on 25 August 2026 · They may change