Constitution Day of the Republic of Indonesia2026 · Date · History · Messages
Indonesian government statistical-agency pages identify 18 August as Constitution Day of the Republic of Indonesia and describe it as an annual commemoration.
About Constitution Day of the Republic of Indonesia
Indonesia observes Constitution Day on 18 August under Presidential Decree No. 18 of 2008.
The decree expressly states that Constitution Day is not a public holiday.
Why Constitution Day of the Republic of Indonesia matters
The date commemorates the constitutional step taken on 18 August 1945, when the Preparatory Committee for Indonesian Independence established the 1945 Constitution as the constitution of the Republic.
The legal observance itself was designated much later, in 2008. Keeping those dates separate avoids presenting the 1945 constitutional event as if it were also the date the recurring modern observance was legally created.
History of Constitution Day of the Republic of Indonesia
On 18 August 1945, the Preparatory Committee for Indonesian Independence established the 1945 Constitution.
Presidential Decree No. 18 of 2008 was signed on 10 September 2008 and designated 18 August as Constitution Day.
The decree also states that Constitution Day is not a holiday from work, and it took effect on 10 September 2008.
What the evidence establishes
Confirmed institutional roles and milestones are shown first. Details that could not be established from the reviewed sources are listed separately below.
5 fields not established in reviewed sources
Also known as
Indonesia Constitution Day
How to Observe Constitution Day of the Republic of Indonesia
Read the 2008 decree to see both the designated date and the explicit non-holiday clause.
Use Constitutional Court materials to study the constitutional history around August 1945.
When writing about the observance, distinguish “Constitution Day” from Indonesia’s Independence Day on 17 August.
Avoid calling 18 August a public holiday when the establishing decree explicitly says otherwise.
Constitution Day of the Republic of Indonesia Facts
Constitution Day is fixed on 18 August.
Presidential Decree No. 18 of 2008 established the observance.
The decree was signed and took effect on 10 September 2008.
The decree expressly says Constitution Day is not a public holiday.
The date refers to the constitutional action of 18 August 1945.
Constitution Day of the Republic of Indonesia Messages
May Constitution Day of the Republic of Indonesia be approached with accurate historical context, careful sourcing and respect for people who understand the history differently.
Topic and context
What this page does not assume
- Keep the source-defined country, community, organizer or institutional scope; do not silently broaden it.
- Do not treat the title alone as proof of government recognition or public-holiday status.
- Do not add a creator, founding story or origin claim unless the supporting evidence establishes it.
- Remembrance Civic Context Care.
Evidence & sources
Sources used across the guide are gathered here. Labels show how each source supports the page, and contextual references are kept separate from primary evidence.
Indonesia BPK legal database — Presidential Decree No. 18 of 2008 on Constitution Day (opens in a new tab)
Indonesia BPK legal database — Presidential Decree No. 18 of 2008 PDF (opens in a new tab)
BPS Batang — Constitution Day of the Republic of Indonesia (opens in a new tab)
National Government
BPS Pandeglang — Constitution Day 2026 (opens in a new tab)
National Government
Constitutional Court of the Republic of Indonesia — constitutional-history publication (opens in a new tab)
Understand it, compare it, then explore further
Start with the most common factual questions, then compare closely related observances and explore useful connections.
Frequently asked questions
When is Constitution Day of the Republic of Indonesia?
18 August annually The documented recurrence rule is: 18 August.
Does Constitution Day of the Republic of Indonesia fall on the same date every year?
Yes. It uses a fixed annual date unless stronger evidence changes the pattern.
Is Constitution Day of the Republic of Indonesia an official public holiday?
The reviewed sources verify it within this scope: Indonesia / civic commemoration. That recognition does not by itself make it a statutory public holiday; the site only makes public-holiday claims when reliable evidence explicitly does so.
Who established or recognizes Constitution Day of the Republic of Indonesia?
The reviewed sources identify President of the Republic of Indonesia as the proclaiming or establishing body.
Is Constitution Day of the Republic of Indonesia international or country-specific?
This observance is specific to Indonesia. Its fuller verified scope is: Indonesia / civic commemoration.
How is this page verified?
The factual information is checked against reviewed sources, including the date pattern, scope and institutional history. This page was checked on 2026-09-09.
When is Indonesia’s Constitution Day?
It is observed on 18 August.
Is Constitution Day a public holiday in Indonesia?
No. Presidential Decree No. 18 of 2008 explicitly states that Constitution Day is not a holiday.
Why is 18 August used?
The decree ties the date to 18 August 1945, when the 1945 Constitution was established as the Constitution of the Republic.
Other observances on August 18
These observances are also listed on August 18, 2027.
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