How to Write a Japanese Email to a Friend or Acquaintance

The register between chat and keigo

Learners usually own two written registers: the clipped casual style of a messaging app and the fixed formulas of business Japanese. The personal email lives between them. It uses desu and masu from the first line to the last, because email is a slightly formal medium even between friends, but it does not use the business frame; nobody writes osewa ni natte orimasu to a friend's mother. The warmth comes from content: remembering something they said, asking after a child's cold, naming the meal they cooked.

The people who get this email are a specific group: a friend you address politely, a former teacher or host family, a colleague you also see socially, an acquaintance from a class or club, or a friend's parents. With a close friend you would normally message instead, and if you do email, plain forms are fine. The business email guide on this blog covers work correspondence, and almost nothing in it transfers here except the habit of one topic per email.

The five-move skeleton

Every personal email in Japanese can be built from five moves. First, a greeting matched to how long it has been since you were last in touch. Second, one line about the other person, a question or a remembered detail, before you talk about yourself. Third, your news or the purpose of the email, in a short paragraph. Fourth, a closing wish about their health, the season or a next meeting. Fifth, your name, on its own line. The moves are short; a whole email is often eight lines.

The second move is the one learners skip, and it is what separates a letter from a notice. It signals that you thought about the reader before you started typing. Keep it specific and answerable. Vague lines such as ogenki desu ka on their own are fine as a greeting but weak as this move; ask about the thing they mentioned last time.

A greeting matched to how long it has been

The opening line tells the reader how long the gap has been, and choosing the wrong one feels odd, like saying long time no see to someone you met yesterday. Within a couple of weeks of meeting, konnichiwa plus your name, or senjitsu wa arigatō gozaimashita if they did something for you, is right. After a month or more, ohisashiburi desu is friendly and gobusata shite imasu slightly more formal and apologetic, suited to someone older. A first email to an acquaintance opens with an apology for the suddenness and a reminder of where you met.

Seasonal openers in one sentence

Business letters open with fixed seasonal phrases; personal emails open with one natural sentence about the weather where you are, usually ending in ne so the reader can agree. It sits after the greeting and before the line about the other person, and in a quick reply it can be dropped entirely. Pick the line that matches the month you are writing in, and adjust it if you live in a region where the season arrives earlier or later. The seasonal greetings guide covers the events themselves; here you only need the sentence.

Asking a favour by email

Email is a kind medium for a favour because the reader can decline without facing you. The Japanese shape is a signal that a request is coming, jitsu wa onegai ga atte, then the request in the itadakemasen ka form with a condition attached, moshi gotsugō ga yokereba, then an explicit exit, muzukashikereba enryo naku itte kudasai. The exit is not optional politeness; it is what makes a yes genuine, because the reader knows a no was available.

Keep the favour concrete: what, when, how long, and what you will do in return or how you will make it easy. A vague tetsudatte kudasai asks the reader to guess the size of the commitment, and most people answer vagueness with a polite delay. Expect a reply that either accepts with a small condition or declines with a reason and mata no kikai ni; both are complete answers, and neither needs chasing.

Replying to an invitation

An invitation by email deserves a reply within a day or two even if you are not yet sure, because the host is counting places. Accept with thanks for the invitation, a clear yes, and a practical question, which shows you are really coming. Decline with sekkaku, the word that acknowledges the effort behind the invitation, a short reason or none, zannen desu, and a request to be invited again. The invitations guide on this blog covers the spoken version; in writing the same moves simply become full sentences.

Thanking someone after a visit

A short thank-you email the day after a meal or a stay is commonly expected from a guest, and it is one of the easiest emails to write well because the content is already there. Name the occasion, name one specific thing you enjoyed, send regards to anyone else in the household, and offer a next meeting. The specific detail is what makes it land: oryōri ga oishikatta desu is polite, but naming the gyōza tells them you remember. Send it within a day or two; a week later it needs an apology attached.

Sending photos and attachments

Photos after an outing are a natural reason to email rather than message, especially with older recipients or when there are many files. Say in the body what you attached and roughly how many, warn if the files are large or split across emails, and invite them to say if anything will not open. If a photo shows other people, it is considerate to mention that you have not shared it elsewhere. A reply about photos can be one warm line; you are not obliged to comment on each one.

Openers, closers and sign-offs by distance

Two things move as distance grows. The opener adds humility, from genki to gobusata shite imasu to the respectful irasshaimasu ka. The closer shifts from a plan to meet again to a wish for their health, and the sign-off grows from a nickname to a full name. Japanese emails do not add a separate best regards line; the closing wish is the regards, and the name comes straight after it. Leaving the name off is the commonest learner slip, because chat apps never need it.

A full model email, line by line

This email goes to a colleague's family who hosted you for dinner last week. It thanks them, attaches photos, shares a piece of news, asks after a child, and offers a return invitation, in eleven lines. Notice the order of moves, the single seasonal line at the close rather than the open, and the full name at the end. Copy the skeleton and swap the details for your own.

Saying it aloud when you next meet

An email to someone you see in person is half of a conversation, and the other half happens at the next meeting. They will thank you for it, you will refer to what you wrote, and someone will mention the photos. Learners who write good emails often freeze here because the vocabulary is the same but the medium has changed. These are the spoken lines around a personal email, from asking for an address to apologising for a slow reply; say them at conversational speed, not reading pace.