Our C corp became a large corporation. Can we use last year's tax for every estimated installment?
A large corporation has restricted use of prior-year tax for estimated installments.
By AE Tax Advisors Team · Updated October 29, 2026
A large corporation has restricted use of prior-year tax for estimated installments. The rules generally permit limited first-installment reliance with a required later catch-up, rather than using prior-year tax for every payment. Large-corporation status has a specific historical taxable-income test, including applicable aggregation rules.
A specific business-owner situation
A growing corporation relies on last year's tax throughout a strong current year. If it meets the large-corporation definition, that approach can underpay later required installments.
Illustrative example, not a client result.
What to establish before filing
- Test historical large-corporation status.
- Apply the limited prior-year rule.
- Calculate catch-up and remaining installments from the permitted methods.
Which fact changes the answer?
A corporation meeting the statutory historical-income test differs from one outside it. The status can persist even when this year's income declines.
A mistake to avoid
Do not decide large-corporation status solely from current revenue or number of employees.
Records that support the decision
- Historical taxable-income records.
- Controlled-group information.
- Installment calculation.
The decision to document
Document the status test and give treasury a payment schedule that incorporates the required catch-up rather than a flat prior-year percentage.
Business-owner tax planning and preparation scope · Discuss advisory scope with AE
Related questions
- Our C corp sold a major asset in June. Can annualized estimated tax spread the gain evenly across the year?
- Our C corp substantially overpaid estimates. Must we wait for the completed income-tax return to seek a refund?
Sources and editorial context
- IRS Publication 538: accounting periods and methods
- IRS Form 2220 instructions: corporate estimated-tax installments
General educational information prepared with AI assistance. No individual professional review is claimed. Apply the relevant tax-year rules to the actual records. Editorial policy · AI disclosure.