O número está no comprovativo.

Because está is used for location or a current state.

In O número está no comprovativo, the sentence is saying where the number is located: it is on/in the receipt/proof document.

• estar = to be, in a temporary state or location
• ser = to be, for identity, definition, origin, permanent characteristics, etc.

So:

• O número está no comprovativo. = The number is on the receipt/document.
• O número é importante. = The number is important.

Using é here would sound wrong because you are not defining the number; you are saying where it is.

No is a contraction of:

• em
  • o = no

So:

• em o comprovativo → no comprovativo

This is very common in Portuguese. A few similar contractions are:

• em + a = na
• em + os = nos
• em + as = nas

So no comprovativo literally means in/on the document. In natural English, you would usually translate it as on the receipt or on the proof/confirmation document, depending on context.

Portuguese uses definite articles more often than English.

So O número means the number, and it sounds natural because it refers to a specific number already understood in the situation.

Compare:

• O número está no comprovativo. = The number is on the receipt/document.
• Número on its own would usually not work as a full subject in this sentence.

In Portuguese, articles are very normal before nouns, much more than in English.

Because número is a masculine noun in Portuguese.

That is why it takes:

• o número
• not a número

Its adjective or article must agree with it in gender and number.

Some examples:

• o número
• um número
• os números

This is something you simply learn with the noun. The ending -o often suggests masculine gender, though there are exceptions in Portuguese.

In European Portuguese, comprovativo usually means a supporting document, proof, or receipt/confirmation document, depending on context.

It is often used for things like:

• proof of payment
• bank transfer confirmation
• receipt
• official proof that something happened

So O número está no comprovativo could mean things like:

• The number is on the receipt.
• The number is on the proof of payment.
• The number is on the confirmation document.

A useful note for learners: in Brazilian Portuguese, comprovante is often more common than comprovativo in this sense. In Portugal, comprovativo is very natural.

Literally, em often corresponds to in, on, or at, depending on the context.

With documents, English usually prefers on:

• O número está no comprovativo. → The number is on the receipt/document.

But Portuguese uses em more broadly, so you do not need to choose differently in Portuguese. No comprovativo is the normal phrase.

The accent in está shows that the stress falls on the last syllable:

• es-TÁ

Without the accent, esta would be a different word, usually meaning this (feminine), as in:

• esta casa = this house

So the accent is important because it distinguishes:

• está = is
• esta = this

In European Portuguese, the pronunciation is roughly:

• está ≈ sh-TAH or es-TAH, depending on speech and region

The unstressed first vowel is often reduced in European Portuguese.

This is the most neutral and common word order in Portuguese:

• subject: O número
• verb: está
• location/complement: no comprovativo

So it follows a straightforward Subject + Verb + Complement pattern.

You could change the order for emphasis, for example:

• No comprovativo está o número.

But that sounds more marked or literary. For normal everyday speech, O número está no comprovativo is the natural choice.

Yes, possibly — but it depends on what kind of document you mean.

• recibo = receipt
• comprovativo = proof/confirmation/supporting document

If the document is specifically a receipt, recibo may be the best word. If it is more general proof — for example, proof of payment or a transfer confirmation — comprovativo may be more accurate.

So both can be correct, but they are not always interchangeable.

Yes, it is natural and correct in European Portuguese.

It sounds like something you might hear in practical situations such as:

• customer service
• banking
• online payments
• forms and registrations
• receipts and confirmations

For example, someone might say it when explaining where to find a reference number, payment code, or transaction number.

Yes. In this sentence, o número is general and can refer to many kinds of numbers depending on context, such as:

• a transaction number
• a reference number
• an invoice number
• an order number
• a tax number
• a confirmation number

Portuguese often leaves this unspecified if the situation already makes it clear. If needed, you could be more specific:

• O número de referência está no comprovativo.
• O número da transação está no comprovativo.
• O número da fatura está no comprovativo.