Moj otac kaže da je štedni račun koristan čak i kad na njega možeš uplatiti samo malo novca.

Moj otac is in the nominative because it is the subject of the sentence.

• moj = my
• otac = father

Both are masculine singular nominative, so they match.

Croatian usually keeps the possessive adjective before the noun here, just like English:

• moj otac = my father

After verbs like kaže (says), Croatian very often uses da to introduce a subordinate clause.

So:

• Moj otac kaže = My father says
• da je štedni račun koristan = that a savings account is useful

This is very similar to English that.

Je is the 3rd person singular present form of biti (to be).

In this clause, the subject is štedni račun, which is singular, so the verb must also be singular:

• štedni račun je koristan = the savings account is useful

When this becomes part of the larger sentence, it stays:

• kaže da je štedni račun koristan

Štedni račun means savings account.

It is made of:

• štedni = savings / saving
• račun = account

The adjective štedni agrees with račun:

• masculine
• singular
• nominative

So it works like a normal adjective + noun combination in Croatian.

Koristan is an adjective meaning useful, and it must agree with štedni račun.

Since račun is:

• masculine
• singular
• nominative

the adjective is also:

• koristan

Compare:

• račun je koristan = masculine singular
• knjiga je korisna = feminine singular
• pismo je korisno = neuter singular

Čak i kad means even when or, depending on context, even if.

• čak i adds emphasis: even
• kad means when
• kada is the longer form of kad

In most cases, kad and kada mean the same thing. Kad is very common in everyday language and is fully normal here.

So:

• čak i kad... = even when...

This is because Croatian says uplatiti na račun = to pay/deposit into an account.

Here:

• na = onto / into in this banking expression
• njega = him/it in the accusative form of on

It refers back to račun, which is masculine:

• račun → na njega

So:

• na njega možeš uplatiti... = you can deposit ... into it

Even though njega can mean him, here it clearly means it, because it refers to račun.

Not necessarily. Croatian often uses the 2nd person singular in a general sense, just like English you.

So možeš here can mean:

• you can in the general sense
• one can in more formal English

It does not have to mean the speaker is addressing one specific person.

Uplatiti is the perfective form, and uplaćivati is the imperfective form.

Here, uplatiti is used because the sentence is talking about the possibility of making a deposit, viewed as a complete action:

• možeš uplatiti = you can deposit

If you used uplaćivati, it would sound more like repeated or ongoing depositing:

• možeš uplaćivati = you can keep depositing / deposit regularly

Both can make sense in some contexts, but uplatiti is very natural here.

Because malo here means a little / only a small amount of, and expressions of quantity in Croatian are usually followed by the genitive.

So:

• malo novca = a little money

Here:

• malo = quantity word
• novca = genitive singular of novac

That is why it is not mali novac.
Mali novac would literally mean small money, which is not how Croatian expresses a little money.

Because it follows the quantity word malo.

This is a very common Croatian pattern:

• puno vode = a lot of water
• malo vremena = a little time
• dosta posla = enough work
• malo novca = a little money

So the genitive here is triggered by the quantity expression, not by the verb.

No, Croatian word order is fairly flexible, although some versions sound more natural than others.

This sentence is natural as written:

• čak i kad na njega možeš uplatiti samo malo novca

Placing na njega before the verb helps keep the phrase uplatiti na njega together in meaning and also sounds smooth in context.

Croatian often moves parts of the sentence around for emphasis, rhythm, or information structure, more freely than English does.