You are about to pay for something on a Japanese online shopping site. You tap the big button on the product page — and it says 購入する（こうにゅうする）. You think: “Wait, isn’t the word for ‘buy’ just 買う（かう）?” Later, at a ramen shop, you need to tell the server what you want. Your textbook said to use 注文する（ちゅうもんする）. And when you message a friend to say you are heading to the mall, you realize you need yet another word: 買い物（かいもの）. Four different situations, four different words — and you only practiced one.
Japanese has a surprisingly rich vocabulary for buying and shopping, and the differences are not just about formality. 買う refers to the act of acquiring a specific item; 購入する is its formal twin, used in business and on commercial platforms; 買い物する describes the activity of shopping itself; and 注文する covers the process of placing an order — from restaurant meals to online goods. This guide breaks down all four verbs, explains when each one fits, and adds the bonus vocabulary that fills out the picture: 支払う（しはらう）, 決済する（けっさいする）, 注文済み（ちゅうもんずみ）, 購入済み（こうにゅうずみ）, and more.
By the end you will know exactly which verb to reach for at the checkout counter, the restaurant table, and the online cart — and you will understand why Japanese EC sites say 購入する while your friend texts 買い物してきた.
| Verb | Reading | Core meaning | Typical context | Register | JLPT |
|---|---|---|---|---|---|
| 買う | かう | Buy (a specific item) | Daily conversation, any item | Casual / neutral | N5 |
| 購入する | こうにゅうする | Purchase (formally) | Business, EC sites, high-value goods | Formal / written | N3 |
| 買い物する | かいものする | Go shopping / do shopping | Shopping as an activity | Casual / neutral | N5 |
| 注文する | ちゅうもんする | Order (food, goods, services) | Restaurant, online order, procurement | Neutral to formal | N4 |
YukaI tried to say “I bought a new phone” to my Japanese colleague and used 購入しました. She laughed a little — was that wrong?
ReiNot wrong exactly, but a little stiff for casual conversation! 購入しました sounds like you are filling out a warranty form. With a colleague you’d normally just say 買いました. Think of 購入 as the “official” version you see on buttons and receipts.
What Does 買う Mean?
買う（かう）is the everyday Japanese verb for “to buy.” It is a Group 1 (godan / u-verb), making its て-form 買って and its past tense 買った. If you can only learn one shopping verb, this is the one — it covers casual purchases of any kind, made by any person, in any setting. You use it to buy a coffee, a train ticket, a souvenir, a car. There are almost no situations where 買う would be factually wrong, though in formal writing or on commercial platforms, 購入する is preferred.
One important note for English speakers: 買う takes the direct object particle を, not に. The item being purchased is marked by を, and the place of purchase is marked by で. The person you buy from is marked by から.
Example 1 — basic purchase:
コンビニでサンドイッチを買いました。
Konbini de sandoicchi wo kaimashita.
I bought a sandwich at the convenience store.
Example 2 — buying for someone:
妹（いもうと）にプレゼントを買ってあげた。
Imouto ni purezento wo katte ageta.
I bought a present for my younger sister.
Example 3 — asking about a purchase:
どこでその帽子（ぼうし）を買ったの？
Doko de sono boushi wo katta no?
Where did you buy that hat?
Example 4 — planning a future purchase:
来週、新しいギターを買うつもりです。
Raishuu, atarashii gitaa wo kau tsumori desu.
I’m planning to buy a new guitar next week.
Compound words built on 買う
買う sits at the root of a wide family of compound words you will encounter constantly in daily life.
買い物（かいもの） — shopping (noun); the activity of buying things
買い手（かいて） — buyer, purchaser (the person who buys)
買い替える（かいかえる） — to replace something by buying a new one (e.g., 古い冷蔵庫を買い替える — replace an old refrigerator)
買い占める（かいしめる） — to buy up, to corner the market
買い値（かいね） — purchase price (the price the buyer pays)
衝動買い（しょうどうがい） — impulse buying
まとめ買い（まとめがい） — bulk buying, stocking up
What Does 購入する Mean?
購入する（こうにゅうする）is the formal, Sino-Japanese equivalent of 買う. Both verbs describe the same transaction — exchanging money for goods or services — but 購入する signals that the context is official, commercial, or written. You will see it on EC site buttons (購入する / 購入手続きへ), on receipts, in user manuals, in business emails, and in product warranty registration forms. You will also hear it in formal speech, such as announcements at electronics stores or real estate consultations.
A key feature of 購入する is that it tends to imply a considered or significant transaction — not a quick snack grab. While you can say コンビニで飲み物を購入した, it sounds oddly solemn, as if you are writing a report about it. Save 購入する for situations that warrant the formality.
Example 5 — EC site button / formal written context:
このボタンを押すと購入手続き（こうにゅうてつづき）が完了（かんりょう）します。
Kono botan wo osu to kounyuu tetsuzuki ga kanryou shimasu.
Pressing this button will complete your purchase process.
Example 6 — high-value item:
先月、マンションを購入しました。
Sengetsu, manshon wo kounyuu shimashita.
Last month, I purchased a condominium.
Example 7 — business context:
弊社（へいしゃ）では新しいソフトウェアを購入する予定です。
Heisha dewa atarashii sofutowea wo kounyuu suru yotei desu.
Our company plans to purchase new software.
Example 8 — user registration / warranty form:
ご購入日（こうにゅうび）をご記入（きにゅう）ください。
Go-kounyuu-bi wo go-kinyuu kudasai.
Please fill in your date of purchase.
Key compound words built on 購入
購入済み（こうにゅうずみ） — already purchased (the -済み suffix means “done / already completed”)
購入履歴（こうにゅうりれき） — purchase history (on an EC site account page)
購入日（こうにゅうび） — date of purchase
購入金額（こうにゅうきんがく） — purchase amount
購入手続き（こうにゅうてつづき） — purchase procedure / checkout process
予約購入する（よやくこうにゅうする） — to pre-order (literally “reservation purchase”)
The -済み（ずみ）suffix is worth pausing on. It attaches to the stem of a noun or verb to mean “already done.” 購入済み means the item has already been bought. You will see it in your account status, on delivery tracking pages, and in order confirmations. Its counterpart for orders is 注文済み（ちゅうもんずみ）— already ordered.
What Does 買い物する Mean?
買い物する（かいものする）shifts the focus from buying a specific item to the activity of shopping itself. Where 本を買う means “buy a book” (one item, one transaction), 買い物に行く means “go shopping” (an activity that may involve many stores and many items). This distinction matters in conversation: 何を買いましたか（what did you buy?）asks about a specific item, while どこで買い物しましたか（where did you go shopping?）asks about the overall trip.
買い物 can be used as a noun on its own (買い物に行く — go shopping; 買い物が好き — like shopping) or as a compound verb by attaching する (買い物する — to do shopping, to shop). Both forms are common in everyday speech.
Example 9 — shopping as an activity:
週末（しゅうまつ）に友達（ともだち）と買い物に行きました。
Shuumatsu ni tomodachi to kaimono ni ikimashita.
I went shopping with a friend on the weekend.
Example 10 — asking about shopping:
今日、買い物してきた？
Kyou, kaimono shite kita?
Did you go shopping today?
Example 11 — describing a routine:
母（はは）は毎週土曜日（まいしゅうどようび）にスーパーで買い物します。
Haha wa maishuu doyoubi ni suupaa de kaimono shimasu.
My mother goes shopping at the supermarket every Saturday.
Example 12 — declining or expressing preference:
オンラインショッピングより、実際（じっさい）に店（みせ）で買い物するほうが好きです。
Onrain shoppingu yori, jissai ni mise de kaimono suru hou ga suki desu.
I prefer actually going shopping in stores to online shopping.
Useful shopping vocabulary built on 買い物
買い物リスト（かいものリスト） — shopping list
買い物袋（かいものぶくろ） — shopping bag
買い物客（かいものきゃく） — shopper, customer (in a store)
買い物カゴ（かいものカゴ） — shopping basket (also used for online cart)
買い物に行く（かいものにいく） — to go shopping
ウィンドウショッピング — window shopping (loanword, also written as ウィンドーショッピング)
YukaSo if I want to say “I’m going to the department store to buy a coat,” should I use 買いに行く or 買い物に行く?
ReiBoth work, but they have a slightly different feel. コートを買いに行く（かいにいく）means you are going specifically to buy a coat — one target item. デパートに買い物に行く suggests you are going on a general shopping trip, and buying a coat might be part of that. If you know exactly what you want and that’s the mission, 買いに行く is more precise. If it’s more of a browse-and-see outing, 買い物に行く fits better.
What Does 注文する Mean?
注文する（ちゅうもんする）means “to order” — to make a request for food, goods, or services. The critical difference from 買う and 購入する is timing: 注文する describes the request itself, not the completed exchange of money for goods. When you 注文する at a restaurant, the food has not yet arrived. When you 注文する online, the package has not yet shipped. The purchase may or may not be complete. This forward-looking quality makes 注文する the right verb for anything that involves a waiting period between request and delivery.
注文する is neutral to slightly formal and works across a wide range of contexts: restaurants, online shopping, business procurement, and custom orders. In casual speech, the short form 頼む（たのむ） is sometimes used instead, especially at restaurants, but 注文する is always safe and natural.
Example 13 — restaurant order:
ラーメンを注文しました。
Raamen wo chuumon shimashita.
I ordered ramen.
Example 14 — online shopping order:
ネットで靴（くつ）を注文したので、明日届く（とどく）予定です。
Netto de kutsu wo chuumon shita node, ashita todoku yotei desu.
I ordered shoes online, so they should arrive tomorrow.
Example 15 — business procurement:
部品（ぶひん）を五十個（ごじゅっこ）注文してください。
Buhin wo gojukko chuumon shite kudasai.
Please order fifty parts.
Example 16 — custom order:
このケーキは特別（とくべつ）に注文したものです。
Kono keeki wa tokubetsu ni chuumon shita mono desu.
This cake was specially ordered.
Key compound words built on 注文
注文済み（ちゅうもんずみ） — already ordered (order placed, awaiting arrival)
注文番号（ちゅうもんばんごう） — order number
注文履歴（ちゅうもんりれき） — order history (on an EC site account page)
注文確認（ちゅうもんかくにん） — order confirmation
注文内容（ちゅうもんないよう） — order details
ご注文（ごちゅうもん） — your order (polite prefix ご, used by restaurant staff and customer service)
注文を取る（ちゅうもんをとる） — to take an order (said of waitstaff)
買う vs 購入する: Casual vs Formal
買う and 購入する describe the same action. The choice between them is almost entirely a question of register — the formality level appropriate to the situation.
Use 買う in everyday conversation: talking to friends and family, texting, telling someone what you picked up at the store, or narrating your own daily experience. It is the natural, default choice for all casual and neutral contexts.
Use 購入する in formal and commercial contexts: EC site buttons, purchase confirmation emails, business reports, formal letters, user registration forms, receipts, and customer service conversations. It is also appropriate when the item being purchased is significant — real estate, electronics, a vehicle — even in somewhat formal spoken contexts.
Casual context — use 買う:
コンビニで飲み物買ってきた。
Konbini de nomimono katte kita.
I picked up a drink at the convenience store.
Same action, formal context — 購入する sounds wrong here:
❌ コンビニで飲み物を購入してきました。
This is not wrong per se, but it sounds bizarrely formal — like writing a field report about a vending machine interaction.
Formal / commercial context — use 購入する:
下記（かき）のボタンから購入手続きへお進みください。
Kaki no botan kara kounyuu tetsuzuki e o-susumi kudasai.
Please proceed to the purchase process using the button below.
High-value item in spoken conversation:
先日、新しい車を購入しました。
Senjitsu, atarashii kuruma wo kounyuu shimashita.
The other day, I purchased a new car.
(Acceptable: a car is a major purchase and a slightly elevated register feels natural.)
| Situation | Natural choice | Awkward choice |
|---|---|---|
| Telling a friend what you bought at 7-Eleven | 買う | 購入する (too stiff) |
| EC site checkout button | 購入する | 買う (too casual for a button label) |
| Explaining a laptop purchase in a business email | 購入する | 買う (not formal enough for professional writing) |
| Asking a child “Did you buy candy?” | 買う | 購入する (strangely formal for a child) |
| Reporting a major equipment purchase at work | 購入する | 買う (too casual for a business report) |
買う vs 買い物する: One Item vs The Activity
This distinction trips up many learners because both verbs involve buying things. The key is scope. 買う focuses on a specific item: 本を買う (buy a book), ケーキを買う (buy a cake). There is one item and one act of purchasing. 買い物する, by contrast, describes shopping as an ongoing activity — a trip to the stores, a session of browsing and buying, a Saturday morning routine at the market. The specific items matter less than the fact that shopping is happening.
Think of it this way: 何を買いましたか（What did you buy?）is asking about a specific item. どこで買い物しましたか（Where did you go shopping?）is asking about an outing. Both questions are about shopping, but they probe different aspects of the experience.
Specific item — 買う:
本屋（ほんや）で新しい漫画（まんが）を買った。
Hon-ya de atarashii manga wo katta.
I bought a new manga at the bookstore.
Shopping activity — 買い物する:
午後（ごご）ずっと渋谷（しぶや）で買い物していた。
Gogo zutto Shibuya de kaimono shite ita.
I was shopping in Shibuya all afternoon.
Both in the same sentence:
買い物に行って、ジャケットを買ってきた。
Kaimono ni itte, jaketto wo katte kita.
I went shopping and bought a jacket.
Notice that in the last example, both verbs appear naturally together. 買い物に行く sets the activity frame (“I went on a shopping trip”), and 買う names what was acquired within that trip. This is a very natural pattern in everyday Japanese.
One more useful contrast: you can say 何も買わなかった（I didn’t buy anything）perfectly naturally. But 買い物した without buying anything? Technically fine — you went shopping and left empty-handed — and native speakers do say 見るだけで買い物した（I went shopping just to browse / literally “I shopped just by looking”), though 見るだけにした（I just looked）is more common. The point: 買い物する can happen even without a completed purchase.
注文する vs 購入する: Order vs Completed Purchase
This is the distinction that confuses learners most on EC sites — and it is a real and important difference. 注文する describes the request stage: you have clicked “place order,” your card has been charged (or will be charged), but the goods have not yet arrived. 購入する describes the completed transaction: the item is yours. In EC site account pages, you will often see both terms because they refer to different moments in the buying lifecycle.
Here is how the timeline works for a typical online purchase:
1. カートに入れる — Add to cart
2. 注文する — Place the order (request sent, payment authorized)
3. 注文確認メール — Order confirmation email received
4. 発送される — Item ships
5. 届く — Item arrives
6. 購入済み — Purchase complete (item in your possession)This is why EC site account menus show both 注文履歴（ちゅうもんりれき）and 購入履歴（こうにゅうりれき）. 注文履歴 is your list of all orders placed — including ones in transit or pending. 購入履歴 specifically refers to completed purchases. In practice many platforms use 注文履歴 for both, but when both terms appear, they carry this distinction.
Example 17 — order placed, not yet arrived:
昨日注文した本はまだ届いていません。
Kinou chuumon shita hon wa mada todoite imasen.
The book I ordered yesterday hasn’t arrived yet.
Example 18 — purchase complete:
先週購入したパソコンが今日届きました。
Senshuu kounyuu shita pasokon ga kyou todokimashita.
The laptop I purchased last week arrived today.
Example 19 — 注文済み vs 購入済み on a status page:
このアイテムは注文済みです。配送（はいそう）をお待ちください。
Kono aitemu wa chuumon-zumi desu. Haisou wo o-machi kudasai.
This item has been ordered. Please wait for delivery.
このアイテムは購入済みです。ダウンロードできます。
Kono aitemu wa kounyuu-zumi desu. Daunrōdo dekimasu.
This item has been purchased. You can download it.
(Common for digital goods like e-books and software.)
支払う and 決済する: Two more payment verbs
While 購入する describes the overall purchase transaction, two more verbs focus specifically on the money side of the exchange.
支払う（しはらう） — to pay. This is the everyday verb for paying money. It covers cash, card, and any method of handing over funds. 支払う focuses on the act of giving money, not on what you receive in return.
クレジットカードで支払いました。
Kurejitto kaado de shiharaimashita.
I paid by credit card.
決済する（けっさいする） — to complete payment / to check out. 決済 is slightly more formal and technical than 支払い. It appears in financial contexts, on EC checkout screens (お支払い方法 / 決済方法), and in business accounting. Think of it as “process the payment” or “settle the account” rather than the simple act of handing over money.
クレジットカードで決済する場合はこちらをご選択ください。
Kurejitto kaado de kessai suru baai wa kochira wo go-sentaku kudasai.
Please select this option if paying by credit card.
In summary: 注文する = place the order; 購入する = the overall purchase is complete; 支払う = pay the money; 決済する = process the payment (formal/technical).
YukaSo on an EC site, I might see all four words — 注文する, 購入する, 支払う, and 決済する — on the same page?
ReiExactly! A typical Japanese checkout flow might say 注文を確認する (review your order), then 購入する (complete the purchase), then ask you to choose a 決済方法 (payment method), and confirm the 支払い金額 (amount to pay). Each word is doing a different job in the same process.
Decision Rule: Which Shopping Verb Should You Use?
Use this flowchart to choose the right verb in any shopping situation.
Are you describing the activity of shopping (a trip, a session, a habit)?
YES → 買い物する
(買い物に行く / スーパーで買い物する / 買い物が好き)
NO ↓
Are you describing placing an order — food, online goods, a custom item?
YES → 注文する
(ラーメンを注文する / ネットで注文する / 部品を注文する)
NO ↓
Are you in a formal/commercial context — EC site, business, written document,
high-value item, or official transaction?
YES → 購入する
(ご購入ありがとうございます / パソコンを購入する / 購入履歴)
NO ↓
Everyday conversation — one item, casual register?
YES → 買う
(コンビニで買う / 友達に買ってあげる / 何を買ったの？)A few extra rules of thumb to remember:
● If you are not sure whether to use 買う or 購入する, start with 買う. It is never incorrect — it may just be less formal than expected in a particular context.
● 注文する is for requests with a delivery gap. If the item is right in front of you and you pick it up and pay, you 買う — not 注文する.
● 買い物する never takes a direct object with を. You cannot say ❌ 本を買い物した. Buy the book: 本を買った. Go shopping and buy a book: 買い物に行って本を買った.
● 購入済み and 注文済み both use the -済み suffix — but 購入済み means you have the item; 注文済み means you have placed the order and are waiting.
Quick Quiz
Test yourself with these five questions. Choose the most natural verb or expression for each blank.
1. You are telling your friend you went shopping at the mall today.
今日ショッピングモールで_____した。
(a) 購入 (b) 買い物 (c) 注文
Answer: (b) 買い物 — You are describing a shopping activity, not a single purchase. 買い物 is the activity-focused word. 購入 would need する and sounds bizarrely formal for a casual conversation about your afternoon. 注文 is for placing orders, not describing a shopping trip.
2. At a ramen shop, the server comes to your table. You want to place your order.
すみません、_____してもいいですか？
(a) 買い物 (b) 購入 (c) 注文
Answer: (c) 注文 — At a restaurant, you 注文する to place a food order. 買い物 is shopping as an activity. 購入 is for formal commercial purchases, not restaurant ordering.
3. An EC site account page shows a list of things you have bought in the past. What is the label likely to say?
(a) 買い物リスト (b) 購入履歴 (c) 注文履歴
Answer: (b) 購入履歴 or (c) 注文履歴 — both are valid. On Japanese EC sites, 注文履歴 typically shows all orders (including in-transit items), while 購入履歴 emphasizes completed transactions. Both labels are commonly used. If forced to pick one for “things you have bought,” 購入履歴 is slightly more specific to completed purchases.
4. You are filling in a warranty card for a new camera. The form asks for the date you bought it.
ご_____日をご記入ください。
(a) 注文 (b) 買い物 (c) 購入
Answer: (c) 購入 — Official forms use 購入 for the date of purchase. ご購入日（こうにゅうび）is the standard term. 注文日 refers to the order date, which may be different from when you received the item. 買い物日 is not a standard term.
5. You ordered a jacket online three days ago and it has not arrived yet. Which sentence is more natural?
(a) 先日ジャケットを購入しましたが、まだ届いていません。
(b) 先日ジャケットを注文しましたが、まだ届いていません。
Answer: (b) 注文しました — Because the item has not arrived yet, the process is not complete. 注文する captures this in-transit state perfectly. (a) with 購入する is not unnatural — you could argue the purchase is “done” in the sense that you paid — but 注文した is the more precise and natural word when you are emphasizing that it has not arrived yet. You will see (b) used in customer service emails and inquiries.
Are you practicing with Japanese shopping apps or EC sites? Have you spotted 注文履歴 and 購入履歴 in the same account menu? Drop a comment below — we’d love to hear how you have been encountering these words in real Japanese!
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