How do you invoice in a public tender?

Bill in a public tender ... Wow, it is not something that you learn in one day or that you can improvise on the march. And, of course, it depends a lot on the country and its rules, but the basic roll almost always looks like: you have to soak up the contract, know exactly how much everything costs (without making balls), and follow the government billing rules to the letter, which are usually more strict than the math teacher.

First, don't doubt it: you have to read the contract as if it were the last book on Earth. There they tell you when, how and why you must send the invoice. It is not "I send it to you when I can", but there are very clear dates and formats. And, yes, every time you send an invoice, it has to come with all the info: what did you sell, how much, how much does everything cost, the total ... the complete menu.

And eye, there is no space to invent prices. What you put in the contract, that is. Neither more nor less. If you were wrong to calculate, then bad luck, because changing it later is an impossible mission. Therefore, you have to review all the numbers well before sending anything, which then comes the dramas.

Another thing: the issue of electronic invoice. It is not optional in most countries already, it is what there is. You need a system that is approved by the Government and that draws the invoices with all the mandatory data: your RFC, the date, the detail of what you sold, the total and, if applied, the VAT. If you forget something, get ready to reject it and have to start over. A headache, believe me.

Save everything. But everything, huh? The invoices, the acknowledgs, the deliveries, to the confirmation mails. You never know when they will ask you for evidence that you deliver what you promised. Better to have it and not need it, than the opposite.

In summary: Billing in a public tender is a mixture of being meticulous, never trusting you and following the rules to the letter. If you don't want problems, do it well from the beginning. And well, if you want to continue playing in the world of tenders, you better get used to this level of detail, because here they do not forgive even a poorly invoiced penny.