The 180-day (6-month) extension is the lowest per-month cost on the Cambodia Business eVisa for stays under a year — cheaper per month than stacking shorter extensions.
Lodged direct at the MFAIC counter in Phnom Penh, the 180-day extension fee is $100–150 USD (~$152–229 AUD), cash on lodgement.
Routed through a registered Phnom Penh agent the same extension lands at $170–200 USD (~$259–305 AUD) all-in — a service margin of $50–70 USD (~$76–107 AUD) buys you the trip handling and the agent paperwork.
The multi-entry add-on is roughly $50 USD (~$76 AUD) extra and pays for itself on the first re-entry — the alternative is buying a fresh Business eVisa at $90 USD (~$137 AUD).
The 180-day tier is renewable once for another 180 days in-country, giving Aussie consultants close to 13 months of legal stay on a single original Business eVisa.
This guide is for the Aussie consultant, contractor, or sponsored business traveller who is already in Phnom Penh on a Business eVisa and has decided the 6-month bracket is the right call. If you have not yet booked the underlying visa, the Cambodia Business visa for Australians anchor walks through the upfront application; the wider Cambodia Business eVisa extensions guide compares all four lengths (1, 3, 6, 12 months) side by side.
Documents Aussie consultants need to lodge the 180-day
Your Australian passport — physical, signed, with at least 6 months of validity beyond the 180-day extension end date. If your passport expires inside that window, renew with DFAT first.
Your current Cambodia Business eVisa — the printed PDF you arrived on, with the entry stamp from Phnom Penh airport (KTI) clearly visible.
One recent passport-style photo — 4cm × 6cm, plain white background, taken in the last six months, head and shoulders only.
An employer or sponsor letter if your project is sponsored — short single-page letter on letterhead from the Cambodian or international entity engaging you, confirming the engagement, dates, and your role. Not always asked for, but routinely accepted when offered, and it smooths edge-case questions.
Payment — clean US cash for the MFAIC route ($100–150 USD or ~$152–229 AUD), or per the agent's preferred method (cash is universal, bank transfer is sometimes available).
A completed extension form — the same bilingual one-pager used for the shorter tiers, available at the MFAIC counter or downloadable from MFAIC.
The employer letter question comes up most often. Strictly, the 180-day extension can be lodged without one — the agent or counter will accept the file without an employer letter and the application will run. Practically, an Aussie consultant on a sponsored engagement is better off including a short one-pager from the engaging Cambodian or international entity. It confirms the engagement is real, removes any edge-case question about why a 6-month extension is needed, and is the single piece of paper that can convert a borderline file into a routine one. The cluster on long-stay business extensions has more on the sponsor-letter framing.
Multi-entry, renewal, and the close-to-13-month stay path
If you are weighing the 6-month renewal against simply flying out and back in on a fresh Business eVisa, the extension-vs-fresh-eVisa decision piece is the place to read next, and the multiple-rounds extension guide covers what happens if you want to push past the renewal cap into a third 180-day round.
Three real Aussie consultant scenarios on the 180-day tier
When the 180-day is the wrong tier for your Aussie trip
The other framing question Aussies hit is whether to extend at all or simply book a fresh Business eVisa for the second 6-month block. For most cases the in-country extension is cheaper and less disruptive, but the calculus flips if you were going to be back in Australia anyway for a partner meeting or a family event. The extension-vs-fresh-eVisa comparison is the dedicated piece on that decision.
Pulling it together for your 2026 6-month Cambodia engagement
The short summary for Aussies: the 180-day extension is the per-month value tier for half-year stays on the Cambodia Business eVisa. MFAIC counter route is $100–150 USD (~$152–229 AUD); agent route is $170–200 USD (~$259–305 AUD) and worth the margin for most consultants. Multi-entry adds roughly $50 USD (~$76 AUD) and pays for itself on the first out-and-back trip. The tier is renewable once for another 180 days, taking you close to 13 months on the original visa. For the wider apply or extend decision, the visa cost guide for Australians and the Australia country pillar cover the upstream numbers.
If you have not yet booked the underlying Business eVisa, start there. $90 USD (~$137 AUD) all-in, approved in 3 business days, delivered as a printable PDF by email, with free resubmission if Immigration flags a correction and Aussie-timezone support across the flight. The how-to-apply walkthrough has the field-by-field detail, and the business meeting trip guide covers the wider trip-planning brief.
How much is the Cambodia 180-day Business visa extension for Australians?
Two prices to know. Direct at the MFAIC counter in Phnom Penh, the lodgement fee for the 180-day extension is $100–150 USD (~$152–229 AUD), paid in clean US cash. Routed through a registered Phnom Penh agent, the same extension lands at $170–200 USD (~$259–305 AUD) all-in — the $50–70 USD (~$76–107 AUD) service margin covers the counter trips and paperwork handling on your behalf. Multi-entry adds roughly $50 USD (~$76 AUD) on top of either route.
Why is the 6-month tier the per-month value sweet spot?
Run the maths. Six stacked 30-day extensions at $50 USD each is $300 USD (~$457 AUD) for 180 days. Two stacked 3-month extensions at $120 USD each is $240 USD (~$366 AUD). The single 180-day extension at the $125 USD midpoint is $125 USD (~$190 AUD) at the counter — less than half the stacked-30s cost for the same legal cover. For Aussie consultants on 6-month engagements, the 180-day tier is the cheapest legal route in-country.
What documents do I need for the 180-day extension?
Your Australian passport with at least 6 months of validity beyond the extension end date, your current Business eVisa printout, a recent 4cm × 6cm passport-style photo on a plain white background, an employer or sponsor letter if your project is sponsored (single page, on letterhead, in English), payment in clean US cash, and a completed bilingual extension form. The sponsor letter is not strictly mandatory but smooths edge-case questions and is worth including if you have one.
How long does the 180-day extension take to process?
At the MFAIC counter: 2 to 3 working days from lodgement to pick-up. Through a Phnom Penh agent: 7 to 10 working days end-to-end, because the agent batches counter trips and adds a paperwork-check step on either side. Lodge at least 2 to 3 weeks before your current Business eVisa expires to keep margin in hand for the upper end of either window. The new extension back-dates to the day after your current visa expires, so there is no gap.
Is multi-entry worth the extra $50 USD (~$76 AUD)?
On a 180-day extension, almost always yes. Without multi-entry, the extension is single-entry, which means exiting Cambodia at any point during the 180 days burns the extension. To re-enter you would need a fresh Business eVisa at $90 USD (~$137 AUD) and a new 30-day clock. The multi-entry premium of roughly $50 USD (~$76 AUD) pays for itself on the first out-and-back trip and saves the new visa hassle. Take multi-entry unless you genuinely will sit in Phnom Penh for the full six months.
Can the 180-day extension be renewed?
Yes — once in-country, for a further 180 days. The renewal lodgement is the same paperwork at the same MFAIC counter or through the same agent, the renewal fee broadly matches the original at $100–150 USD (~$152–229 AUD) at the counter or $170–200 USD (~$259–305 AUD) through an agent, and the renewal start date back-dates to the day after the current extension expires. Stacked with the original 30-day Business eVisa and the first 180-day extension, the renewal gives you close to 13 months of continuous legal stay.
Do I need an employer letter for the 180-day extension?
Not strictly. The 180-day extension can be lodged without an employer letter and the application will run. Practically, if your Cambodia stay is for a sponsored consulting, audit, or advisory engagement, including a short single-page sponsor letter on letterhead is the lowest-effort way to convert a borderline file into a routine one. Three sentences are enough: who is engaging you, what the engagement is, and the dates.
Can I switch from a Tourist visa to the 180-day Business extension once I am in Cambodia?
No. Visa-class conversion inside Cambodia is not supported for Australians on the eVisa system. The 180-day extension is only available on the Business eVisa (E-Class). If you arrived on a Tourist eVisa and need a longer stay for paid work, meetings, supplier visits, or due-diligence, you must exit Cambodia and re-enter on a fresh Business eVisa before any extension can be lodged. The Tourist eVisa has been a hard 30-day stay since November 2025.
What if my project ends early and I do not need the full 180 days?
You can simply leave Cambodia. There is no exit penalty for using less than the authorised stay, and there is no refund either — the $100–150 USD (~$152–229 AUD) counter fee is fully sunk. If your project has a more than one-in-four chance of ending early, the 3-month tier with the option to renew if it runs is the lower-regret pick. The 180-day tier rewards commitment; pick it when the engagement is firm.
