Termingebyret betales hver måned.

Because termingebyret is the definite singular form of the noun termingebyr.

• et termingebyr = an installment fee / a periodic fee
• termingebyret = the installment fee / the fee

The ending -et is typical for many neuter nouns in Bokmål when they are definite singular.

This whole word is also a compound noun:

• termin = installment period / due period / term
• gebyr = fee

So termingebyr literally means something like installment fee or periodic fee, depending on context.

The -s marks the passive voice in Norwegian.

So:

• betaler = pays / is paying
• betales = is paid

In this sentence, Termingebyret betales hver måned means that the fee is paid every month.

This -s passive is very common in Norwegian, especially in:

• formal language
• instructions
• rules
• banking and administrative texts

It often sounds a bit more impersonal than an active sentence.

Yes. Betales is present tense passive.

Compare:

• betaler = pays / is paying
• betales = is paid
• ble betalt = was paid
• har blitt betalt = has been paid

So betales hver måned means is paid every month or gets paid every month.

Yes, often you could.

These are both possible:

• Termingebyret betales hver måned.
• Termingebyret blir betalt hver måned.

The difference is mostly about style:

• betales sounds more formal, concise, and written
• blir betalt sounds a bit more neutral or spoken

In notices, contracts, and banking language, the -s passive is especially common.

Because hver måned means every month or each month, and Norwegian does not use an article there.

• hver = every / each
• måned = month

So:

• hver måned = every month

This works similarly to English. You would not say every the month, and Norwegian also does not add a separate article here.

Because after hver, Norwegian normally uses the indefinite singular form of the noun.

So:

• hver måned = every month
• not hver måneden

This is a common pattern:

• hver dag = every day
• hver uke = every week
• hvert år = every year

Notice that the noun after hver/hvert is not definite.

Good question. The form depends on the gender of the noun that follows.

• måned is a masculine noun in Bokmål
• so we use hver måned

Compare:

• hver dag = every day
• hver uke = every week
• hvert år = every year

So:

• hver is used with common-gender nouns in many everyday cases
• hvert is used with neuter nouns, such as år

Since måned is not neuter, hver måned is correct.

The sentence follows normal Norwegian main-clause word order:

• Termingebyret = subject
• betales = verb
• hver måned = time expression

So the structure is:

Subject + verb + time expression

That is very natural in Norwegian:

• Regningen betales i dag. = The bill is paid today.
• Husleien betales hver måned. = The rent is paid every month.

Yes. That is exactly how the passive works here.

The sentence does not say who pays it. It only says what happens to the fee:

• Termingebyret betales hver måned. = The fee is paid every month.

If you want to mention the person, you would normally use an active sentence, for example:

• Kunden betaler termingebyret hver måned. = The customer pays the fee every month.
• Du betaler termingebyret hver måned. = You pay the fee every month.

So the passive keeps the focus on the fee, not on the payer.

Not exactly.

• hver måned means every month / each month
• i måneden or om måneden can sometimes mean per month or a month

For example:

• Det betales hver måned. = It is paid every month.
• Det koster 500 kroner i måneden. = It costs 500 kroner per month.

So in your sentence, hver måned emphasizes the regular repeated timing.

Yes, very much so.

This kind of sentence is typical in:

• bank documents
• invoices
• payment plans
• contracts
• official information

That is because:

• termingebyret is a financial/administrative word
• betales uses the formal -s passive

A more everyday spoken version might be something like:

• Du betaler termingebyret hver måned.
• Man betaler termingebyret hver måned.

But the original sentence sounds natural and normal in formal written Norwegian.