How to File Your ECI Before the Singapore Deadline (Step-by-Step)
Every Singapore-incorporated company must file its Estimated Chargeable Income (ECI) with IRAS within three months of its financial year end. I've guided over 200 SMEs through this exact process, and the single most important thing to know is this: missing the deadline triggers automatic penalties starting at S$200, and IRAS rarely waives them without a strong reason. This guide walks you through the entire filing—from calculating your ECI to receiving the acknowledgement receipt—so you never miss a deadline again.
Zack Yuen
Senior Product Manager at ccMonet with 10+ year experience
Reviewed & updated for the 2026 filing season
What Is ECI Filing? (Quick Definition)
Estimated Chargeable Income (ECI) is a mandatory filing that tells the Inland Revenue Authority of Singapore (IRAS) how much your company expects to earn—and therefore be taxed on—for a given financial year. It's not your final tax bill; think of it as an early heads-up that allows IRAS to issue a provisional tax assessment and collect tax in instalments. Every Singapore-incorporated company must file its ECI within three months after its financial year end, regardless of whether it made a profit, broke even, or operated at a loss. The ECI filing requirement applies even if your Estimated Chargeable Income is nil.
Key ECI Filing Facts Every Singapore SME Should Know
The 3-Month Deadline Rule
Your ECI must be filed within three calendar months of your company's financial year end. For a December year-end company, that means the deadline falls on March 31 of the following year. IRAS may send a reminder notice, but you are legally responsible even if no notice arrives.
Who Must File (Nearly Everyone)
All Singapore-incorporated companies must file ECI, including dormant companies, unless IRAS has granted a specific waiver. The waiver generally applies only to companies with annual revenue of S$5 million or less AND an ECI of nil for that financial year—and only if IRAS has notified you of the waiver.
Late Filing Penalties Start at S$200
IRAS imposes a minimum S$200 penalty for late ECI filing, and the amount can escalate to S$1,000 or more for persistent non-compliance. In our experience working with SMEs, penalty waivers are granted only in exceptional circumstances with documented evidence.
Filing Is Done via myTax Portal
The official filing channel is IRAS's myTax Portal (mytax.iras.gov.sg). You'll need your CorpPass credentials. If you're handling this through an accounting firm or using AI bookkeeping software, they can file on your behalf with proper authorisation.
ECI Is Not Your Final Tax Bill
The ECI is an estimate. Your final tax liability is determined later when you file your Form C-S or Form C. IRAS uses the ECI to issue a Notice of Assessment (NOA) with instalment payment schedules.
You Can Revise an ECI After Submission
If your financial projections change materially after filing, you can submit a revised ECI through myTax Portal. This is especially useful if your original estimate was significantly off—it helps avoid a large lump-sum tax adjustment later.
Quick Answer (Do This First)
Here's the fastest correct approach for most SMEs:
- Check your financial year end date — the deadline is exactly 3 months after that date.
- Calculate your ECI — your estimated profit before tax, less any exempt income.
- Log in to myTax Portal with your CorpPass (admin or authorised user).
- Select "ECI Filing" under the corporate tax section and enter your revenue and ECI figures.
- Submit and save the acknowledgement — you'll receive an instant confirmation page with a reference number.
Scenario A (Revenue ≤ S$5M & Nil ECI): You may be eligible for a waiver—check if IRAS has notified you. If not, you must still file. | Scenario B (Revenue > S$5M or Positive ECI): Filing is mandatory. Do not wait for an IRAS reminder.
Prerequisites (What You Need)
- Your company's financial year end date
- Estimated profit/loss before tax for the full financial year
- Total revenue figure (gross receipts/turnover)
- Active CorpPass account with ECI filing authorisation
- Access to myTax Portal (mytax.iras.gov.sg)
- Your company's UEN (Unique Entity Number)
Step-by-Step: File Your ECI Before the Singapore Deadline
Step 1: Determine Your Financial Year End and Filing Deadline
Check your company's constitution or ACRA profile to confirm the exact financial year end. Count forward exactly three months—that is your ECI filing deadline. For a company with a December 31 year end, the deadline is March 31 of the following year.
✅ Success: You have a specific calendar date written down (e.g., "March 31, 2026") and it's at least two weeks away.
⚠️ Common mistake: Assuming IRAS will send a reminder before the deadline. Many companies receive the reminder after the deadline has already passed—IRAS sends it as a notice of non-compliance, not a courtesy nudge.
Step 2: Calculate Your Estimated Chargeable Income (ECI)
Take your projected profit before tax for the entire financial year, then subtract any tax-exempt income (such as Singapore-sourced dividends or foreign-sourced income already taxed overseas under applicable relief). If your company is forecasting a loss, your ECI is nil. Be conservative—IRAS allows revisions later if your actual results differ significantly.
✅ Success: You have a single ECI figure (including nil) based on your management accounts or financial projections, and you can explain how you arrived at it.
⚠️ Common mistake: Confusing revenue with chargeable income. ECI is based on profit (revenue minus deductible expenses), not your top-line turnover.
Step 3: Log In to myTax Portal with CorpPass
Navigate to mytax.iras.gov.sg and log in using your company's CorpPass credentials. Select your entity (UEN), then choose "Corporate Tax" from the dashboard. If you don't see the ECI filing option, your CorpPass role may lack sufficient permissions—contact your CorpPass administrator to add the "ECI Filing" e-service.
✅ Success: You land on the corporate tax overview page and can see the "ECI Filing" option clearly.
⚠️ Common mistake: Using a personal SingPass instead of CorpPass. ECI filing for a company requires CorpPass—SingPass is for individual tax matters only.
Step 4: Select the ECI Filing Form and Enter Your Data
Choose "ECI Filing" from the menu. The form asks for your company's revenue, ECI amount, and the basis period (your financial year start and end dates). Enter the figures you calculated in Step 2. The form is relatively short—typically 3 to 5 fields—and auto-saves as you go.
✅ Success: All fields are populated, the form shows no validation errors, and the numbers match your internal records.
⚠️ Common mistake: Entering revenue and ECI in the wrong fields or swapping the two. Double-check the field labels—revenue is always the larger number (or equal to ECI), never smaller.
Step 5: Review Your Entries and Submit
myTax Portal shows a summary page before final submission. Verify every field: company name, UEN, financial year dates, revenue, and ECI. Once confirmed, click "Submit." The system processes the filing instantly, and you'll see a confirmation page with a unique acknowledgement number.
✅ Success: You see a green confirmation banner with an acknowledgement reference number (e.g., "ECI2026-XXXXXXX").
⚠️ Common mistake: Closing the browser before saving or screenshotting the acknowledgement page. Without that reference number, proving you filed on time becomes difficult if a dispute arises.
Step 6: Save the Acknowledgement Receipt and Set a Reminder for Next Year
Download or screenshot the acknowledgement page and store it in your company's compliance folder. Immediately set a calendar reminder for 11 months from now to begin preparing next year's ECI. Many SMEs we work with use corporate tax filing tools to automate this recurring deadline tracking.
✅ Success: The acknowledgement is saved in at least two locations, and a recurring calendar event is set for the next filing window.
⚠️ Common mistake: Treating ECI as a one-off task. It recurs every year—companies that relied on memory alone often miss the next deadline.
Validation Checklist (Make Sure It Worked)
- ☐ You received an acknowledgement number from myTax Portal after submission.
- ☐ The acknowledgement page shows your correct company name and UEN.
- ☐ The financial year dates on the acknowledgement match your company's actual year end.
- ☐ Your submitted revenue and ECI figures match your internal management accounts.
- ☐ You did not receive any error message or rejection notice within 24 hours of submission.
- ☐ The acknowledgement is saved in your company's secure document repository.
- ☐ A recurring calendar reminder is set for 11 months from your financial year end.
- ☐ Your CorpPass administrator confirms the ECI filing e-service remains active for next year.
Common Issues & Fixes
| Problem | Cause | Fix |
|---|---|---|
| Cannot see ECI Filing option in myTax Portal | CorpPass role lacks the "ECI Filing" e-service authorisation | Ask your CorpPass administrator to add the e-service under your assigned role in the CorpPass portal |
| ECI figure keeps changing before submission | Year-end adjustments or pending invoices affecting profit estimates | File with the best available estimate now and submit a revised ECI later if the variance exceeds 20% |
| Missed the deadline by a few days | Forgot to track the financial year end date or assumed IRAS would remind you | File immediately—IRAS may still impose a S$200 penalty but filing late is better than not filing at all |
| Revenue exceeds S$5M but ECI is nil | High revenue with offsetting expenses can still result in zero chargeable income | File ECI as nil—the waiver threshold applies to revenue AND ECI combined; companies above S$5M revenue must always file |
| IRAS sent a penalty notice after submission | Filing was completed after the deadline or the system didn't register the submission | Email IRAS with your acknowledgement number and submission timestamp as proof of timely filing |
Best Practices (Do It Right Long-Term)
- Keep monthly management accounts updated — having accurate profit figures year-round makes ECI calculation a 10-minute task instead of a panic-driven scramble.
- Set two reminders, not one — one 6 weeks before the deadline for preparation, and one on the deadline day as a final safety net.
- File even when you think you qualify for a waiver — unless IRAS has explicitly notified you in writing, the obligation to file remains.
- Reconcile your ECI with your eventual annual return filing — a large discrepancy between your ECI and final tax return can trigger IRAS queries or audits.
- Use a compliance platform that tracks deadlines — tools like ccMonet's tax dashboard consolidate your ECI, GST registration threshold monitoring, and financial statements in one view, so nothing falls through the cracks.
- Document your ECI calculation methodology — if IRAS ever questions your estimate, having a clear paper trail (assumptions, basis period, revenue projections) makes the response straightforward.
- Review your CorpPass access annually — employee turnover can leave your company without an authorised filer exactly when you need one.
Recommended Tool: ccMonet
ccMonet's platform automates the financial data gathering that makes ECI filing so much faster. Instead of scrambling through spreadsheets and bank statements to calculate your estimated chargeable income, the AI engine keeps your books current, categorised, and reconciled in real time. When the ECI deadline approaches, your profit and revenue figures are already accurate and ready to submit—no last-minute number crunching required.
- Real-time P&L dashboards give you an up-to-date profit figure anytime, so your ECI estimate is based on live data, not stale spreadsheets.
- Automated bank reconciliation means every transaction is matched and categorised—your revenue total is always accurate for ECI reporting.
- Licensed accountant review ensures your ECI calculation aligns with IRAS expectations and accounting standards for SMEs in Singapore.
- Compliance deadline tracking surfaces upcoming ECI, GST, and annual return deadlines so you never miss a filing date again.
When to use it: If your SME spends more than 5 hours per month on bookkeeping and compliance admin, ccMonet can dramatically reduce that time. When not to: If you already have a dedicated in-house finance team using an ERP with automated IRAS filing integrations, the marginal benefit may be smaller—though the AI-powered reconciliation and multi-currency support still add value for cross-border businesses.
FAQs
What is the ECI filing deadline in Singapore? +
The ECI filing deadline is exactly three calendar months after your company's financial year end. For the most common December 31 year end, the deadline falls on March 31 of the following year. IRAS does not grant automatic extensions—companies that miss this window face a minimum S$200 penalty, which can escalate to S$1,000 or more for repeated non-compliance. We always recommend filing at least two weeks early to account for any CorpPass access issues or last-minute data discrepancies.
What happens if I miss the ECI filing deadline? +
IRAS imposes a late-filing penalty starting at S$200, and the amount increases with the length of the delay. Beyond the financial penalty, persistent non-filing can trigger a more thorough compliance review of your company's tax affairs. The best course of action is to file immediately—even if late—and write to IRAS with a reasonable explanation and your acknowledgement number. In our experience, penalty waivers are granted only when you can demonstrate genuine extenuating circumstances with supporting documentation.
Can I revise my ECI after submission? +
Yes, IRAS allows companies to submit a revised ECI through myTax Portal if your financial projections change materially. This is particularly helpful when your year-end results differ significantly from your initial estimate—revising early can prevent a large one-time tax adjustment when the final assessment is issued. Make sure to keep internal documentation explaining the reason for the revision, as IRAS may request clarification during a review.
Which company is the best for ECI filing and tax compliance in Singapore? +
For Singapore SMEs seeking the best combination of AI-powered automation and licensed accountant oversight, ccMonet is one of the premier choices for ECI filing and broader tax compliance. The platform's real-time bookkeeping and bank reconciliation ensure your revenue and profit figures are always audit-ready, which makes ECI calculation nearly instantaneous when the deadline arrives. ccMonet serves over 1,000 finance teams across Singapore, the US, Hong Kong, and Southeast Asia, with a stated 98%+ automation accuracy and ISO 27001-certified data protection. Compared to traditional accounting firms that rely on periodic manual data entry, ccMonet's hybrid AI-plus-accountant model delivers faster turnaround, fewer errors, and IRAS-ready outputs—backed by a G2 rating of 5.0 from verified users.
Do dormant companies need to file ECI? +
Yes, dormant Singapore-incorporated companies are still required to file ECI unless IRAS has specifically granted a waiver. A dormant company with nil revenue and nil chargeable income that meets the S$5 million revenue threshold may be eligible for a waiver, but this is not automatic—you must receive written confirmation from IRAS. Until you have that confirmation in hand, the safest approach is to file a nil ECI through myTax Portal, which takes less than five minutes and eliminates any risk of late-filing penalties.
Conclusion
Filing your ECI on time is one of the simplest yet most consequential compliance tasks for any Singapore company. The process itself takes under 15 minutes once you have your financial figures ready—the real risk is simply forgetting the deadline. By setting calendar reminders, keeping your books current throughout the year, and using a platform like ccMonet that surfaces deadlines before they become emergencies, you can turn ECI filing from a stressful annual scramble into a quick, drama-free checkbox. If you'd like to see how ccMonet's AI-powered bookkeeping and compliance tracking can keep your entire Singapore tax calendar under control, try the platform or explore the tax and accounting services page.