ただし / もっとも: How to Add a Proviso or Qualification in Japanese
ただし and もっとも are qualifying conjunctions: each lets the preceding statement stand, then narrows or concedes part of it instead of contradicting it.12 ただし adds a proviso or exception. もっとも concedes a qualifying "though, mind you." Both lean formal and written, so this page draws the line between them and the plain contrastives しかし / でも / けど.
Overview
These two connectives belong to the same family because neither reverses the sentence before it. The earlier claim survives. The second clause only adds a condition, a carve-out, or a softening reservation. That shared job is what "qualifying" means here. It separates ただし and もっとも from しかし-type forms, which pivot to an opposing point.
Qualify, don't contradict
Both words affirm what precedes and then restrict it. The dictionary defines ただし as a conjunction that「前述の事柄に対して、その条件や例外などを示す」(presents a condition or exception with respect to the preceding matter).1 It defines もっとも as one used「前の事柄を肯定しつつ、例外あるいは一部相反する内容を補足するとき」(when, while affirming the preceding matter, one supplements it with an exception or partially contradictory content).2
The two jobs split cleanly. ただし is the proviso or exception marker, the form that shows a 条件・例外.1 もっとも is the concessive "that said," which the dictionary itself glosses as「とはいうものの。なるほどそうだが。ただし」("that said / true enough, but / however").2
Register and where you meet them
ただし leans formal and written. Its noun form 但し書き is「法規、条約、規約などに多く用いられる」(much used in statutes, treaties, and regulations),4 which makes ただし the default exception marker in rules, notices, contracts, and laws.
もっとも spans a wider register, from conversational to written concession. Its dictionary gloss「とはいうものの／なるほどそうだが」reads as spoken softening as readily as written qualification.2
For level placement, treat this page as N2 because ただし, the harder member of the pair, anchors it there.5 The もっとも conjunction often appears one band earlier, indexed at N3 in standard prep references.6 The JLPT does not publish a per-item grammar list, so these bands are a prep convention rather than an official ruling.
ただし: adding a proviso or exception
What ただし does
A first statement makes a rule or a general claim. ただし then introduces the condition, limit, or exception that constrains it.「前述の事柄に対して、その条件や例外などを示す。しかし」1 The 精選版 dictionary frames the move as adversative-leaning (逆接的): it adds a condition or exception that belongs to the preceding matter.7
Useful English glosses are "however / provided that / but note that." The sentence-initial conjunction (接続詞) use is the main one a learner needs.1
入場自由。ただし、子供はお断り。1
"Admission is free. However, children are not admitted."
The second clause is not an opposing fact; it is a restriction on who the free admission applies to. That is the proviso reading at work.
Form and position
ただし typically opens the second sentence in the frame "A。ただし、B。" A comma follows ただし, and B carries the restriction.1 In statutes and formal or legal documents, it is written with the kanji 但し,48 while hiragana ただし is standard in general modern prose.
The word is built from the adverb ただ ("only, just") plus an emphatic particle し.9 The 大辞泉 note that it is「ただを強めた語」corroborates that ただ base.1 That etymology explains the "only / except that" feel: ただし narrows the scope of the statement it follows.
両議院の議員及びその選挙人の資格は、法律でこれを定める。但し、人種、信条、性別、社会的身分、門地、教育、財産又は収入によつて差別してはならない。8
"The qualifications of members of both Houses and of their electors shall be fixed by law. However, there shall be no discrimination because of race, creed, sex, social status, family origin, education, property or income."
The statute keeps the kanji 但し and the historical kana spelling よつて. This shows the proviso use in its native legal setting.
The legal and contract register: 但し書き
The noun 但し書き names a specific kind of clause:「『但し』の語を書き出しにして、前文の内容などについての説明・条件・例外などを書き添えた文」(a sentence that opens with the word 但し and appends an explanation, condition, or exception to the content of the preceding text).10 Because it is「法規、条約、規約などに多く用いられる」(much used in statutes, treaties, and regulations),4 ただし is the default "exception clause" marker in formal and legal Japanese.
The dictionary records the everyday collocation「契約書の末尾に但し書きを付ける」(append a proviso to the end of a contract).10
In statutory drafting, the 但し書 is the proviso clause set against the 本文, the article's main text. A 但し書 that removes the rule for certain cases often closes with the fixed phrase「この限りでない」("this shall not apply"), as in 民法第11条's proviso「ただし、第7条に規定する原因がある者については、この限りでない。」11
The noun 但し書 is attested as far back as 1893, in 三代目三遊亭円遊's『梅見の薬鑵』:「金網を張る可しと但書が附いて居る」.4
ただし、第7条に規定する原因がある者については、この限りでない。11
"However, this shall not apply to a person for whom there exists a cause stipulated in Article 7."
This is the statutory「但し … この限りでない」exception frame. The main article sets a rule, and the 但し書 carves out the cases the rule will not reach.
もっとも: the qualifying "that said"
What もっとも does
The speaker affirms that A is true, then concedes that A is not the whole picture or adds a softening reservation:「前の事柄を肯定しつつ、例外あるいは一部相反する内容を補足するときに用いる」.2 Dictionaries gloss it as「とはいうものの。なるほどそうだが。ただし。」,2 with 精選版 adding「そうはいうものの。一方で。ただし」.3
Useful English glosses are "that said / mind you / then again / true, but…".
旅行にはみんな参加する。もっとも行かない人も二、三いるが。2
"Everyone is going on the trip. That said, there are two or three who aren't, mind you."
The follow-up clause
The B-clause that もっとも opens often closes with the connective が / けど / けれども, a soft contrastive tail. The 大辞泉 headword example itself ends「…二、三いるが」.2 Both dictionaries also gloss もっとも with けれども-adjacent phrasing (「とはいうものの」「そうはいうものの」),23 which fits that が / けれども close.
日本語を話せます。もっとも、少しだけですが。6
"I can speak Japanese. That said, only a little, mind you."
The opener concedes a reservation. The が tail delivers the soft contrast that the concession set up.
みんなラーメンが好きだ。もっとも、例外もありますよ。6
"Everyone likes ramen. That said, there are exceptions."
Disambiguation: もっとも vs 最も vs もっと
The reading もっとも covers more than one word. Only one of them is the conjunction taught here. The split is by position and meaning.
| Form | Word class | Meaning | Position | Swap test |
|---|---|---|---|---|
| 尤も (もっとも) | conjunction | "that said / although"2 | sentence-initial, joining two sentences | swap with ただし |
| 最も (もっとも) | adverb | "most" (superlative)12 | directly before the gradable predicate it scales | swap with 一番 |
| もっと | adverb | "more" | before a quantity or degree | (no swap; means "further / more") |
The conjunction 尤も opens a clause and could be replaced by ただし.2 The adverb 最も scales the adjective or verb right after it:「比べてみて程度が他のどれよりもまさることを表す。いちばん。何よりも」(it expresses that, on comparison, the degree surpasses any other; "the most, above all").12 もっと is a separate adverb meaning "more." It is not the same word as either 尤も or 最も.
最も信頼できる。12
"(the) most trustworthy."
This fragment shows 最も sitting directly in front of the predicate it scales. Compare it with the clause-opening 尤も in the もっとも examples above. The position tells you which word it is.
Nuance and usage contexts
ただし vs もっとも
ただし restricts or excepts: it states an objective limit, condition, or exception on the rule in A (条件・例外を示す).1 It is also the marker statutes use for carve-outs.4 もっとも concedes or reserves: it is the speaker's softening afterthought, "true, but…," supplementing A with a partial counterpoint (肯定しつつ…補足する).2
Both are glossed near ただし in the dictionaries,23 but the feel differs. ただし is the colder, rule-bound proviso. もっとも is the warmer, speaker-stance concession that invites a が / けど tail.2
Where they sit among the contrastives
The key boundary is contradiction versus qualification. しかし and でも plainly contradict by pivoting to an opposing point. ただし and もっとも qualify, leaving A standing. The dictionary glosses ただし as「しかし」-adjacent1 yet restricts it specifically to「条件や例外」, a proviso rather than a free contradiction.1
The softening contrastives けど / けれど / けれども sit close to もっとも at the clause tail rather than the head. もっとも often closes with a が / けれども tail,2 so it layers a concessive opener onto a けれども-type ending.
Good to know
Don't reach for ただし as a general "but"
A common error is using ただし as a free synonym for しかし to join two simply opposing facts. ただし works only when the second clause is a genuine proviso, condition, or exception to the first, per「前述の事柄に対して、その条件や例外などを示す」.1 A plain opposing fact, such as "today is cold but tomorrow is warm," is contrast, not an exception. It takes しかし rather than ただし. The wrong-form sentence「今日は寒い。ただし、明日は暖かい。」should be「今日は寒い。しかし、明日は暖かい。」when only a contrast is meant. The corrected connective form:
今日は寒い。しかし、明日は暖かい。
"Today is cold. However, tomorrow is warm."
This contrast pair is a teaching example of the dictionary's 条件・例外 restriction,1 not a sentence quoted from a source.
もっとも written 尤も, and its 形容動詞 cousin
The same reading もっとも also heads a 形容動詞 (adjectival noun) meaning "reasonable, natural, justified":「道理にかなっていること。なるほどその通りだと思われること。また、そのさま。当然」.213 Dictionary collocations include「尤もな言い分」(a reasonable argument) and「いやがるのも尤もなことだ」(it is only natural that they would hate it).213
The related ～のももっともだ pattern ("no wonder that, it is only natural that") is indexed at N2 as a distinct grammar item.14 Keep it as a "same word, different job" note: the conjunction 尤も opens a clause, while the 形容動詞 尤も takes な or だ and predicates "reasonable."
A swap test for the もっとも split
"尤も opens, 最も points" keeps the two readings apart. The conjunction 尤も ("that said") opens the second clause and can swap with ただし.2 The adverb 最も ("most") points at the adjective or verb right after it and can swap with 一番.12 If ただし fits the slot, the word is 尤も. If 一番 fits, it is 最も. The mnemonic phrasing is built for this article from the two sourced definitions;212 the underlying contrast is what the dictionaries establish.
See also
- のに: How to Say "Even Though" with Frustration in Japanese (Counter-Expectational)
- ところが / ところで: "However" and "By the Way" in Japanese (Discourse Pivots)
- けど / けれど / けれども: The Soft Contrastive "But" in Japanese
- でも / しかし: Sentence-Initial "But" and "However" in Japanese
- Japanese Conjunctions Overview: Clause-Linkers (接続助詞) vs. Sentence-Connectors (接続詞)