Розрахунковий період тарифікації — один місяць.

A word-by-word breakdown:

• розрахунковий = settlement-related, billing-related, calculation-related
• період = period
• тарифікації = of tariffing / of billing according to a tariff
• один місяць = one month

As a full phrase, it is very official/technical language. Depending on context, a natural English rendering could be The billing period is one month, The settlement period is one month, or The tariff-calculation period is one month.

Because Ukrainian has no articles.

English needs a or the, but Ukrainian usually leaves definiteness to context. So:

• період can mean a period or the period
• місяць can mean a month or the month, depending on context

In this sentence, English normally uses the because it sounds like a definition: The billing period is one month.

Because it is an adjective agreeing with період.

Період is:

• masculine
• singular
• nominative

So the adjective must also be:

• masculine
• singular
• nominative

That gives розрахунковий.

If the noun changed, the adjective would change too. For example:

• розрахунковий період = masculine singular
• розрахункова дата = feminine singular
• розрахункове значення = neuter singular

Because Ukrainian often uses the genitive to mean of ....

So:

• період тарифікації = period of tariffing / billing period

Here тарифікації is the genitive singular form of тарифікація.

This noun + genitive pattern is extremely common in Ukrainian:

• центр міста = city center, literally center of the city
• початок року = beginning of the year
• період тарифікації = period of tariffing/billing

In Ukrainian, the verb to be is often omitted in the present tense, especially in definitions, formal statements, and headings.

So:

• Розрахунковий період тарифікації — один місяць. = The billing period is one month.

The dash marks the relationship between the two parts of the sentence.

This is especially common when one noun phrase is being defined by another. In formal writing, the dash is very natural here.

If you wanted a full verb, Ukrainian would more naturally use something like:

• Розрахунковий період тарифікації становить один місяць. = The billing period amounts to / is one month.

In this dash sentence, it functions as the predicate noun phrase after an omitted to be.

In practice, learners usually understand it as the defining value: one month.

A useful detail: with один місяць, the form you see is the same in nominative and accusative for an inanimate masculine noun, so the surface form does not change.

• один місяць = nominative-looking form
• становить один місяць would also look the same on the page

So the main thing to remember is not the visible ending, but the sentence pattern: this is a definition/equation type sentence.

Because official Ukrainian often prefers to state the quantity explicitly.

• один місяць = one month
• місяць = month / a month

Both may be understandable in context, but один місяць sounds more precise and formal, which fits this bureaucratic style.

In contracts, regulations, tariffs, and technical descriptions, spelling out the exact number is very common.

It is normal, but it sounds formal, administrative, or technical rather than conversational.

Words like розрахунковий and тарифікація belong more to business, telecom, utilities, contracts, billing systems, and official documents.

In everyday speech, people might choose something simpler depending on context, for example:

• Розрахунковий період — місяць.
• Тарифікація проводиться щомісяця.
• Оплата розраховується за місяць.

So the original sentence is natural, but in a clearly official register.

Yes, but the emphasis changes.

The original order:

• Розрахунковий період тарифікації — один місяць.

is a classic definition-style structure: first the term, then its value/definition.

You could also say:

• Один місяць — розрахунковий період тарифікації.

But that sounds more marked and puts emphasis on one month.

A very common alternative with a full verb is:

• Розрахунковий період тарифікації становить один місяць.

That often sounds slightly more like a complete formal sentence.

A helpful stress-marked version is:

розрахунко́вий пері́од тарифіка́ції — оди́н мі́сяць

Approximate pronunciation guide:

• розрахунко́вий = rozz-ra-khun-KO-vyy
• пері́од = peh-REE-od
• тарифіка́ції = ta-ry-fi-KA-tsi-yi
• оди́н мі́сяць = o-DYN MEE-syats

The most important thing is to keep the stress in the right place, especially in пері́од and тарифіка́ції.

Not especially. It is more of a technical or administrative noun.

In many contexts, тарифікація refers to:

• billing by tariff
• charging according to a tariff plan
• tariff-based calculation of cost

So a learner should recognize it, but not expect to hear it constantly in casual conversation. It is much more likely in things like:

• mobile phone plans
• utilities
• internet service terms
• contracts
• official pricing documents