Instrumental Uses at a Glance

This is your one-page map of the instrumental (Croatian instrumental). It is the seventh and last case in the traditional order, and it has a reputation for being a "miscellaneous" case — means, company, place, time, predicate. But there is one contrast at its heart that organises almost everything and that English handles badly, so we lead with that, then lay out the rest in a single scannable table.

The one contrast that matters: tool vs person

English uses the single word "with" for two completely different ideas: "I write with a pen" (a tool) and "I went with a friend" (company). Croatian splits these. A tool or means takes the bare instrumental with no preposition (pišem olovkom). Company — a person you are with — takes s / sa + instrumental (idem s prijateljem). Get this one split right and you have the instrumental's most useful rule.

The logic behind the split is worth seeing, because it makes the rule self-explaining rather than arbitrary. A tool is something you act through — it is an extension of you, not a partner. A companion is a separate person alongside you. Croatian reserves the bare instrumental for the "act-through" idea and adds the preposition s ("with, alongside") only when there is a genuine second party. So the question to ask is not "does English use 'with' here?" — it almost always does — but "is this thing my instrument or my companion?" That question gives you the right answer every time.

The instrumental at a glance

1. Means and tool — bare, no preposition

The instrumental's namesake job: the instrument you use to do something. No preposition — the ending alone says "by means of." English would need with or by.

Transport is a special, very common case of means: how you travel takes the bare instrumental — vlakom (by train), autom (by car), avionom (by plane), autobusom (by bus).

2. Company — s / sa + instrumental

A person (or animal, or thing) accompanying you takes s / sa. Use sa (not bare s) before words starting with s, š, z, ž and a few awkward clusters, for pronounceability — sa mnom, sa Šimom.

3. Static position — nad, pod, pred, za, među

A group of place prepositions takes the instrumental when describing where something rests (no motion). They cover the dimensions around an object: nad (above), pod (under), pred (in front of), za (behind/at), među (among), and iznad / ispod (above/below).

These same prepositions switch to the accusative when there is motion into the position (Stavi knjigu pod stol — "Put the book under the table"). Place vs motion is the recurring two-case-preposition pattern.

4. Route, recurring time, and predicate

Three quieter but very useful jobs round out the case. A path you move along takes the bare instrumental (šetam obalom — "I stroll along the shore"). A recurring time — every Saturday, in the mornings — takes the bare instrumental too (subotom, jutrom). And the instrumental marks a predicate with verbs like postati ("become") and the reflexive baviti se ("to do/practise as an activity").

A note on the forms

The instrumental endings are the most distinctive of all the cases — masculine/neuter -om/-em (gradom, prijateljem), feminine -om (ženom) or -i/-ju for the i-declension (noći / noću), and the collapsed plural -ima/-ama shared with the dative and locative. The full table is on the instrumental forms page.

Common Mistakes

Key Takeaways

• The instrumental's master rule: tool = no s, person = s. Pišem olovkom vs idem s prijateljem.
• Means and transport are bare: olovkom, ključem, vlakom, autom.
• Company takes s / sa (use sa before s, š, z, ž and clusters: sa mnom).
• nad / pod / pred / za / među take the instrumental for static position, the accusative for motion.
• Route (obalom), recurring time (subotom, jutrom), and predicate (postati liječnikom, baviti se sportom) round out the case.