English version comes after Japanese.
｢定期代は全額会社が出してくれるから遠くても気にしなくていい｣と思ってませんか？定期代が多いと社会保険料が増えます。社会保険料の計算には定期代を含めるので、あまりに遠くて金額が大きいと影響はありますね。
It's a common practice in Japan that companies provide their employees with the commutation fees, usually trains and subways. The commutation fees aren't taxable up to JPY 150,000($1,360) per month. People don't care much about the amount but they still should be aware that the commutation fees could rise the social insurance premium.