Kantor Akuntan Publik (KAP) Fiantonius, Asthon, Nasiama (FAN) is a continuation of a former KAP that was established on June 6, 2017 based on deed of establishment No. 32 of Robby Leo Selamat, SH, MKn, which was acquired its business license on July 10,2017, based on Minister of Finance of Republic of Indonesia’s decision letter (Keputusan Menteri Keuangan RI - KMK) No. 680/KM.1/2017. On May 27, 2020, FAN was amended to become the KAP Fiantonius, Asthon, Nasiama based on Notarial Deed No. 1 of the same Notary.

FAN consists of certified public accountants (CPAs) who have extending experience and knowledge on areas of Audit, Corporate Governance, Finance and Tax. FAN-CPAs is a merger of certain sole proprietorship public accountants. We intend to response the fast changing business environment and the related accounting, audit, tax, regulations, principles and even more the laws. In doing so, as an allied rather than a sole proprietor, we believe we will be able to meet the pace of the said dynamics requirements.

Our Vision is:

To be one of the best public accountant office in Indonesia.

Our Mission is:

To provide and help client for the best solutions

Our Goals are:

  • To provide services in audit, accounting, finance in a broad perspective in accordance to the relevant laws.
  • To engage in consulting, supervising, mentoring and to provide services in management, business, finance and accounting.
  • To provide training, educating, and improving of client’s internal audit, accounting, finance, management and other relevant services subject to the relevant laws.


Fiantonius Sihotang M.Ak, CA, CPA
Public Accountant No. AP.1146
MoF RI No. 152/KM.1/2015
Extension: MoF RI No. 771/KM.1/2019
He finished his Degree and Graduate Degree both majoring in Accounting from State University of Indonesia.
He had experienced as an external auditor for 7 years.
He spent his career worked for multi national mining companies as an Internal Auditor for 11 years.

Asthon M.H. Siagian M.Ak, CA, CPA (Managing Partner)
Public Accountant No. AP.1219
MoF RI No. 115/KM.1/2016
Indonesia Financial Services Authority - Otoritas Jasa Keuangan (OJK)
- STTD.AP-01/PM.22/2018 – Capital Market
- STTD.AP-391/PB.122/2018 - Banking

He graduated his degree from State University of Brawijaya and Graduate Degree from Trisakti University both majoring in Accounting.
He worked for Deloitte, one of “Big Four” for almost 7 years as an external auditor.
He also had more than 12 years experienced worked on foreign multi national companies responsible for Finance, Accounting, and Tax. Before joining FAN-CPAs, he opened his sole proprietorship public accountant.

Gabriel Nasiama Kroon CA, CPA
Public Accountant No. AP.1386
MoF RI No. 653/KM.1/2017
Graduated from State University of Hasanuddin with major in Accounting.
He worked for certain public accountants and private companies.
Before joining FAN-CPAs, he opened his sole proprietorship public accountant in 2017.