E-invoice is called as ESF (Электронный счет-фактура) in Kazakhstan.
It is a digital version of paper invoices which are standardized for tax audit purposes by the State Revenue Committee. (Комитет Государственных Доходов, Министерства Финансов Республики Казахстан)
On July 1, 2014, it became possible to issue invoices in electronic form in the Republic of Kazakhstan, on a voluntary basis.
According to the Kazakhstan Tax Code updated on 1 January, 2019, all VAT payers selling goods and providing services must issue electronic invoices via the E-invoicing System (IS ESF).
What is IS ESF?