Child Tax Credit Calculator 2026: Methodology and Sources

Current planning constants used

• Child Tax Credit amount: $2,200 per qualifying child
• Maximum refundable Additional Child Tax Credit: $1,700 per qualifying child
• ACTC earned-income threshold: $2,500
• Phaseout threshold: $400,000 for married filing jointly
• Phaseout threshold: $200,000 for all other supported filing statuses
• Phaseout rate: $50 for each $1,000, or fraction of $1,000, above threshold

Calculation flow

1. Multiply the number of qualifying children by $2,200.
2. Apply the current IRS phaseout threshold based on filing status.
3. Reduce the credit by $50 for each $1,000, or fraction of $1,000, above the threshold.
4. Apply available tax liability to estimate the nonrefundable Child Tax Credit used.
5. Estimate the refundable ACTC as the smallest of unused child credit, the earned-income formula, and the $1,700 per-child refundable cap.

2026 source note

As of April 4, 2026, the IRS materials available for Child Tax Credit planning still point to the current post-2025 structure. We therefore use the current IRS Child Tax Credit page and 2025 Schedule 8812 instructions as the working framework for 2026 planning until the IRS publishes updated instructions for the 2026 tax year.

Assumptions and limits

• The tool is built for qualifying children under the Child Tax Credit rules, not the Credit for Other Dependents.
• Puerto Rico and other special Schedule 8812 cases are outside scope.
• The calculator assumes the user has already identified qualifying children correctly.
• The result is a planning estimate, not a substitute for the final Schedule 8812 worksheets.

Primary sources

• IRS Child Tax Credit page
• IRS Instructions for Schedule 8812 (2025)
• IRS Tax Tips published in 2026 summarizing the current credit structure

Related pages: calculator and guide.

Update policy

We update this methodology when the IRS publishes new Schedule 8812 instructions, changes the Child Tax Credit amount, updates the ACTC refundability limits, or changes the taxpayer identification number requirements tied to the credit.

Interpretation note

The calculator is most useful for seeing which limit is binding: income phaseout, tax liability, or ACTC refundability. That is usually the real planning question before the return itself is prepared.

What the calculator does not model

This methodology does not attempt to reproduce every branch of Schedule 8812, including specialized Puerto Rico treatment, every other-dependent interaction, or every return-preparation edge case tied to taxpayer identification rules. The goal is to make the core child-credit math understandable enough for planning without pretending to replace the final worksheet package.

Estimate quality note

The output is most reliable when the user already knows the number of qualifying children and has straightforward earned income and tax-liability figures. The estimate becomes less exact when the return has unusual credit interactions or when the IRS publishes updated 2026 instructions that change the currently available framework.