La cuenta justificativa estará lista, pues incluirá justificantes de gasto.

Cuenta justificativa is a fairly formal, administrative expression. In Spain, it usually refers to a report or statement submitted to justify how money was spent, especially in public administration, grants, or reimbursements.

Grammatically:

• cuenta is a feminine noun
• justificativa is an adjective agreeing with it

So it is not a casual everyday phrase; it sounds bureaucratic or official.

Because lista agrees with la cuenta justificativa, which is feminine singular.

Agreement works like this:

• la cuenta → feminine singular
• therefore lista → feminine singular too

If the noun were masculine, you would use listo instead.

In Spanish, adjectives often come after the noun, especially when they classify or define the type of thing being talked about.

Here, justificativa is not just adding a descriptive opinion like nice or interesting. It is identifying the kind of cuenta it is: a justifying/supporting account/report.

So cuenta justificativa sounds natural and standard, while putting the adjective first would sound unusual here.

Estará is the future tense of estar, so it means will be.

The form is:

• estar
• estará = he/she/it will be

Here it indicates a future result: the report will be ready.

In other contexts, the future can also express probability, but in this sentence it is a straightforward future.

Incluirá is the future tense of incluir and means will include.

The future ending is attached to the infinitive:

• incluir
• incluirá

So the sentence uses two future forms:

• estará lista = will be ready
• incluirá = will include

This makes the whole sentence sound consistent and forward-looking.

Here pues introduces the reason or explanation. It is similar to because, since, or for in a fairly formal written style.

So the structure is:

• statement: La cuenta justificativa estará lista
• explanation: pues incluirá justificantes de gasto

In this sentence, pues is not a filler word; it is a connector giving the reason.

Yes, in many cases you could say:

La cuenta justificativa estará lista porque incluirá justificantes de gasto.

That would be perfectly understandable.

The difference is mainly one of style:

• porque is the most common everyday word for because
• pues sounds a bit more formal, written, or explanatory

So pues fits well in an administrative sentence like this one.

A justificante is a document that proves, supports, or justifies something. In financial or administrative contexts, it often means:

• a receipt
• proof of payment
• supporting documentation

So justificantes de gasto are documents showing that the expenses were real and can be justified.

This is broader than just receipts. Depending on context, it could include invoices, tickets, payment records, and other proof.

De gasto is being used in a general, classificatory way: expense-related supporting documents or proofs of expenditure.

Compare:

• justificantes de gasto = expense receipts / supporting expense documents in general
• justificantes del gasto = the supporting documents for a specific expense already known to the listener

So without el, the phrase sounds more general and standard.

In Spanish, a singular noun is often used after de to name a category or type.

So de gasto means something like:

• related to expenditure
• for expenses
• expense-related

This is similar to how Spanish often uses singular nouns in fixed expressions, especially in formal or technical language.

You may also see plural forms in other contexts, but justificantes de gasto is a very natural collocation.

La appears because the speaker is referring to a specific cuenta justificativa already known in the context.

But justificantes de gasto is being mentioned as a general type of thing the report will include, so no article is needed.

Compare:

• La cuenta justificativa... = a particular report
• incluirá justificantes de gasto = it will include some expense documents / supporting documents

If you said los justificantes de gasto, it would sound more like specific documents already identified.

They have written accents because in these future forms the stress falls on the last syllable:

• es-ta-RÁ
• in-clui-RÁ

The accent mark shows the correct stress and follows Spanish spelling rules.

This is very common in the future tense:

• estará
• incluirá
• será
• hará

So the accents are not optional; they are part of the correct spelling.

It is grammatically natural, but it sounds formal and administrative rather than conversational.

A native speaker would expect this kind of wording in:

• official emails
• grant documentation
• accounting contexts
• public administration

In casual conversation, people would probably use simpler wording. But for formal Spain Spanish, this sentence sounds completely normal.