Numeral Declension in Russian

In Brief

Russian cardinal numbers change form according to case (the grammatical role shown by a word's ending): с одним другом “with one friend,” без трёх рублей “without three rubles,” and о пяти студентах “about five students.” Один behaves much like an adjective, два, три, четыре form a special group, and пять and many larger numbers have noun-like endings. In a compound number, normally every part that can decline changes: к двадцати двум студентам “to twenty-two students.”

Overview

English number words usually remain unchanged: “two friends,” “with two friends,” “about two friends.” Russian uses declension (changing a word's ending) to show the number's function in the sentence. The noun being counted changes too. Compare два друга “two friends,” с двумя друзьями “with two friends,” and о двух друзьях “about two friends.”

This is a B1 topic because it brings together knowledge that is often learned separately: cardinal numbers, noun endings, adjective agreement, and the six Russian cases. It matters in ordinary situations involving prices, distances, groups of people, documents, statistics, and time. Even if you often hear speakers avoid a cumbersome form, the full system remains important in careful speech and especially in writing.

There are two questions to answer whenever a number is used. First, which case does the sentence require? A preposition such as без requires the genitive, while с meaning “with” requires the instrumental. Second, what pattern does that particular number follow? It is more effective to learn the patterns one, two to four, five to twenty, and compound numbers than to memorize every phrase independently.

How It Works

Start with the case required by the sentence

A noun is a word for a person, place, thing, or idea. A numeral phrase contains both the number and the noun, and another word in the sentence usually determines their case.

Function or trigger	Case	Example	Meaning
subject; no case-triggering preposition	nominative	Три студента пришли.	Three students arrived.
без, “without”	genitive	без трёх студентов	without three students
к, “toward/to”	dative	к трём студентам	to three students
direct object (the person or thing directly affected)	accusative	вижу три дома / трёх студентов	I see three houses / three students
с, “with”	instrumental	с тремя студентами	with three students
о, “about”	prepositional	о трёх студентах	about three students

The nominative and accusative counting patterns are special. In the other cases, the basic practical rule is: decline both the numeral and the noun into the required case. Except after forms of один, the noun is normally plural: к двум новым домам, с пятью новыми коллегами, о двадцати страницах.

Один: adjective-like agreement

Один changes for gender and number as well as case. It agrees with its noun much like an adjective: один стол (masculine), одна книга (feminine), одно окно (neuter), одни часы (plural-only “one clock/watch”).

Case	Masculine/neuter	Feminine	Plural
Nominative	один / одно	одна	одни
Genitive	одного	одной	одних
Dative	одному	одной	одним
Accusative	один/одного; одно	одну	одни/одних
Instrumental	одним	одной (also одною)	одними
Prepositional	одном	одной	одних

The masculine and plural accusative forms depend on animacy (whether the noun denotes a person or animal). Use the nominative-like form with an inanimate noun, вижу один дом, but the genitive-like form with an animate masculine noun, вижу одного друга.

In numbers ending in 1, agreement is controlled by the final один: двадцать один студент, двадцать одна книга, двадцать одно письмо. Eleven is an exception because it is a single numeral, not “ten plus one”: одиннадцать студентов.

Два, три, четыре: the special small-number group

Два has a feminine nominative/accusative form, две. The other forms do not distinguish gender.

Case	2	3	4
Nominative	два / две	три	четыре
Genitive	двух	трёх	четырёх
Dative	двум	трём	четырём
Accusative, inanimate	два / две	три	четыре
Accusative, animate	двух	трёх	четырёх
Instrumental	двумя	тремя	четырьмя
Prepositional	двух	трёх	четырёх

In the nominative and inanimate accusative, 2–4 take a noun in the genitive singular: два дома, три окна, четыре книги. An adjective between them has a special agreement pattern: два новых дома, три больших окна, but commonly две новые книги. With feminine nouns, nominative-plural adjective endings are standard; genitive-plural adjective forms such as две новых книги also occur, particularly in some formal or meaning-based contexts.

In an oblique case—any case other than nominative or accusative—the noun becomes plural and matches the required case: без двух домов, к трём окнам, с четырьмя книгами, о двух друзьях. For animate direct objects, use the genitive-like numeral and a genitive-plural noun: Я вижу трёх друзей “I see three friends.”

Пять through двадцать, and тридцать

The numerals пять–двадцать and тридцать share a largely regular pattern. Their genitive, dative, and prepositional end in -и, while the instrumental ends in -ью.

Case	пять	десять	двадцать	тридцать
Nominative/accusative	пять	десять	двадцать	тридцать
Genitive	пяти	десяти	двадцати	тридцати
Dative	пяти	десяти	двадцати	тридцати
Instrumental	пятью	десятью	двадцатью	тридцатью
Prepositional	пяти	десяти	двадцати	тридцати

In nominative and accusative phrases these numerals require the genitive plural: пять домов, десять книг, двадцать студентов. Unlike 2–4, numbers from 5 upward do not acquire a special animate accusative form: вижу пять домов and вижу пять студентов both use пять. The noun is genitive plural in both phrases.

In other cases, both words match the case: без пяти домов, к десяти книгам, с двадцатью студентами, на тридцати страницах.

Compound numbers

A compound cardinal number contains more than one numerical word, such as двадцать два or сто сорок пять. In standard Russian, each component declines:

Case	22 students	145 pages
Nominative	двадцать два студента	сто сорок пять страниц
Genitive	двадцати двух студентов	ста сорока пяти страниц
Dative	двадцати двум студентам	ста сорока пяти страницам
Instrumental	двадцатью двумя студентами	ста сорока пятью страницами
Prepositional	двадцати двух студентах	ста сорока пяти страницах

In the nominative and inanimate accusative, the last number controls the noun: двадцать один дом, двадцать два дома, двадцать пять домов. Numbers ending in 11–14 take the genitive plural regardless of the final digit: сто одиннадцать домов, not a form based on “one.”

In oblique cases, do not apply the nominative counting rule. The phrase behaves as a unit in the selected case: к двадцати двум домам, not a phrase ending in дома.

Tens and hundreds with irregular stems

Several common forms must be learned separately.

Number	Nominative/accusative	Genitive/dative/prepositional	Instrumental
40	сорок	сорока	сорока
90	девяносто	девяноста	девяноста
100	сто	ста	ста
50	пятьдесят	пятидесяти	пятьюдесятью
60	шестьдесят	шестидесяти	шестьюдесятью
200	двести	двухсот / двумстам / двухстах	двумястами
300	триста	трёхсот / трёмстам / трёхстах	тремястами
500	пятьсот	пятисот / пятистам / пятистах	пятьюстами

For 50–80, both historical parts change: пятьюдесятью рублями. For 200–900, both parts change too, but the exact endings vary by case. These forms deserve focused practice rather than guesswork.

Тысяча, миллион, миллиард

Тысяча, миллион, and миллиард are noun-like number words. Тысяча declines like a feminine noun: тысячи, тысяче, тысячей, о тысяче. Миллион and миллиард decline like masculine nouns: миллиона, миллиону, миллионом, о миллионе. They govern a genitive-plural noun in their basic counting form: тысяча рублей, два миллиона жителей.

When they are part of a larger oblique phrase, decline them as well: с двумя тысячами рублей, о трёх миллионах жителей. Notice that тысяча itself is counted by две: две тысячи, not два тысячи.

Examples in Context

Russian	English	Note
Я пришёл с одним другом.	I came with one friend.	Instrumental; один agrees with masculine друг.
Она разговаривала с двумя друзьями.	She was talking with two friends.	Instrumental plural after двумя.
Нам не хватает трёх рублей.	We are three rubles short.	Genitive after не хватает.
Я отправил письма четырём клиентам.	I sent letters to four clients.	Dative: recipients of the letters.
Мы говорили о пяти студентах.	We talked about five students.	Prepositional after о.
Таблица напечатана на двадцати страницах.	The table is printed on twenty pages.	Prepositional form двадцати.
В комнате два больших окна.	There are two large windows in the room.	Nominative counting phrase; genitive-singular noun.
Я вижу двух новых сотрудников.	I see two new employees.	Animate accusative equals genitive here.
Они купили двадцать четыре стула.	They bought twenty-four chairs.	Inanimate accusative; final 4 controls стула.
Мы встретились с двадцатью четырьмя коллегами.	We met with twenty-four colleagues.	Every numerical component declines.
К ста сорока пяти страницам добавили приложение.	An appendix was added to the 145 pages.	Dative throughout the numeral phrase.
Экскурсия длилась около сорока минут.	The tour lasted about forty minutes.	Около requires genitive; сорок → сорока.
В городе живёт один миллион человек.	One million people live in the city.	Миллион governs genitive plural.
Проект помог двум тысячам семей.	The project helped two thousand families.	Dative двум тысячам and семьям.

Common Mistakes

Leaving the number unchanged

• Wrong: с два друзьями
• Right: с двумя друзьями
• Why: С meaning “with” requires the instrumental. Both the numeral and noun must take instrumental forms.

Keeping the nominative counting form in an oblique case

• Wrong: о трёх студента
• Right: о трёх студентах
• Why: Три студента is the nominative counting pattern. After о, both words are prepositional, and the noun is plural.

Declining only the final part of a compound number

• Wrong: с двадцать двумя коллегами
• Right: с двадцатью двумя коллегами
• Why: In careful standard Russian, every declinable component takes the required case.

Ignoring animacy with 2–4

• Wrong: Я встретил три друга.
• Right: Я встретил трёх друзей.
• Why: A direct object referring to animate beings takes the genitive-like accusative with 2–4.

Treating a number ending in 11 like one ending in 1

• Wrong: двадцать одиннадцать студент
• Right: двадцать один студент, but одиннадцать студентов
• Why: Only a compound numeral whose final word is один triggers singular agreement. Одиннадцать is a single numeral and takes genitive plural.

Using два with a feminine noun

• Wrong: два книги, два тысячи рублей
• Right: две книги, две тысячи рублей
• Why: Use две with feminine nouns in the nominative and inanimate accusative.

Usage Notes

Full declension is the norm in edited writing, prepared speech, and situations where precision matters. Long compound forms can be awkward even for native speakers. In spontaneous conversation, speakers may restructure the sentence, use digits, or choose a simpler approximation rather than pronounce a form such as пятьюстами семьюдесятью шестью. That avoidance does not make an undeclined numeral the neutral written standard.

Stress is part of several forms and may shift: два — двух, три — трёх, пять — пяти, сорок — сорока. Written endings alone are therefore not enough; learn difficult forms with audio when possible.

After полтора “one and a half” and полторы (feminine), the basic phrase uses genitive singular: полтора часа, полторы недели. In oblique cases, both become полутора, and the noun is plural in the required case: с полутора часами, о полутора неделях. This useful pattern is related to numeral declension but does not follow the ordinary 2–4 table exactly.

Approximate quantities can reverse the normal order: человек пять means “about five people,” while пять человек means simply “five people.” The numeral still declines when the sentence requires it: с людьми пятью is theoretically formed but highly marked; ordinary speech normally chooses примерно с пятью людьми “with about five people.”

Beyond the Basics / Advanced Use

Numeral agreement can affect the verb too. A quantified group may take a singular neuter verb when presented as one total or event—Пришло двадцать человек “Twenty people arrived”—or a plural verb when the individuals or their separate actions are foregrounded—Двадцать человек пришли вовремя “Twenty people arrived on time.” Context, word order, animacy, and style all influence this choice; it is not controlled by the numeral alone.

Words such as оба/обе “both” have their own declension: обоих/обеих, обоим/обеим, обоими/обеими. They preserve a gender distinction beyond the nominative: с обоими братьями, but с обеими сёстрами. Collective numerals such as двое, трое, четверо also have special forms (двоих, двоим, двоими) and restricted uses, especially with groups of people, children, and plural-only nouns. They should be learned as a related but separate system.

Fractions and decimals follow additional agreement rules. In две целых пять десятых “2.5,” the decimal names whole units and tenths; with a following measured noun, formal usage often treats the quantity as a fractional expression: 2,5 литра (два целых пять десятых литра). In ordinary speech, decimal notation is frequently read in shortened ways depending on context. Master the cardinal patterns in this article before trying to generalize them to fractions.

For exact years and other calendar expressions, Russian often uses ordinal rather than cardinal structure: в две тысячи двадцать шестом году “in the year 2026.” Only the final ordinal component declines in that construction, while две тысячи remains part of the conventional year name. This contrasts with an ordinary cardinal phrase, where all components decline: с двумя тысячами двадцатью шестью рублями “with 2,026 rubles.”

Practice Tips

1. Build one phrase across six cases. Start with два новых студента, then produce двух новых студентов, двум новым студентам, двух новых студентов, двумя новыми студентами, о двух новых студентах. Repeat with пять and двадцать два.
2. Mark every component. Write a long number in separate boxes, choose the case, and change each box before adding the noun: сто + сорок + пять → ста + сорока + пяти.
3. Practice with information you actually use. Describe prices, page counts, distances, and group sizes from your day. Say each phrase first in the nominative, then after без, к, с, and о.

Related Concepts

• Prerequisite: Numbers 20–1000+ — review how Russian builds tens, hundreds, thousands, and compound cardinal numbers.
• Next step: Ordinal Numbers — learn numbers such as первый and двадцать первый, which generally decline like adjectives.