without delay; promptly; immediately
Formal adverbial phrase used in official, legal, or business contexts to indicate that an action should be taken without any delay. Often found in written instructions or regulations.
契約書に署名の上、遅滞なくご返送ください。
Please sign the contract and return it without delay.
問題が発生した場合は、遅滞なく上
If a problem occurs, report it to your supervisor promptly.
直ちに also means 'immediately' and is formal, but it can imply a sense of urgency or instantaneous action. 遅滞なく emphasizes the absence of delay in a procedural sense.
Standard kanji spelling for this adverbial phrase.
Variant spelling using 無く instead of なく; less common but still encountered.
Compound of 遅滞 (chitai, 'delay') + なく (naku, adverbial form of ない 'not'), literally 'without delay'.