Nouns ending in a consonant followed by -y change the -y to -ies in the plural form.
Itinerary is regular. It follows the -ies Conversion rule.
Use plural verbs: "The itineraries are ready" (not "is ready").
Yes. The plural itineraries is standard across all English variants.
The word itinerary follows the standard English pluralization rule. When forming the plural, itinerary becomes itineraries. This follows the -ies Conversion pattern, which is one of the most common plural rules in English.
Understanding why itinerary becomes itineraries helps with spelling and pronunciation. Nouns ending in a consonant followed by -y change the -y to -ies in the plural form.
When using itineraries in writing, remember that it functions as a plural noun in sentences. It pairs with plural verbs and pronouns. For example: "The itineraries are ready" (not "is ready"). This subject-verb agreement is essential for grammatical correctness.