Interac
Interac is Japan's largest private provider of Assistant Language Teachers, with 3,600 teachers placed in public elementary, junior high, and senior high schools nationwide. It has 50 years in education, 13 regional branches from Sapporo to Fukuoka, and has been wholly owned by Link and Motivation Inc. (Tokyo Stock Exchange: 2170) since 2014. That branch network means placements almost anywhere in Japan — and Interac staff based near you rather than a head office hours away.
You'll be placed in a Japanese public school under contract with the local Board of Education, teaching alongside Japanese Teachers of English. School staff communicate with ALTs in English, and no Japanese is required to do the job well. The schedule is a standard 9–5 built around the Japanese school calendar.
Most assignments are suburban, semi-rural, or in regional cities like Sapporo, Sendai, or Kumamoto rather than central Tokyo or Osaka — which means lower living costs, closer ties to a local community, and usually other ALTs in your town or a neighboring one. Each branch runs regular training events where you'll meet teachers in your area.