Form 5471 – Schedule I‑1, GILTI, Tested Income and QBAI Guide

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Schedule I-1 looks like a worksheet, but it is where each CFC's GILTI inputs get pinned down before they leave for the shareholder return. You report tested income, qualified business asset investment, and tested interest expense in the CFC's functional currency, and those figures feed Form 8992 at the U.S. shareholder level. Get the per-CFC numbers wrong here and the GILTI computation downstream inherits the error.

The arithmetic is unforgiving in small ways: tested income on line 6 equals line 4 minus line 5, and line 9d tested interest expense cannot drop below zero. Category 4, 5a, and 5b filers attach a separate I-1 for each CFC and, where it applies, each separate FTC basket, with conversion to U.S. dollars on the lines the instructions require. Build the controls now and the section 904 and foreign tax credit work later goes faster.

Key Takeaways

• Schedule I‑1 reports each CFC’s tested income or tested loss, QBAI, and tested interest in the CFC’s functional currency, and those figures feed your Form 8992 GILTI computation.
• You do report deductions on Schedule I‑1: line 5 captures deductions properly allocable to the amount on line 4 (gross tested income less exclusions). The U.S. shareholder then computes GILTI on Form 8992, including any Section 250 deduction on Form 8993.
• Category 4 controllers and applicable Category 5 U.S. shareholders must file Schedule I‑1 with Form 5471, attached to the underlying return by its due date, including extensions.
• Report amounts in functional currency on I‑1, then convert specific lines to U.S. dollars using the average exchange rate when required by the instructions and regulations.
• Penalties for late or incomplete Form 5471 filings start at 10,000 per foreign corporation and can escalate, plus potential reductions to foreign tax credits if the failure continues after notice. Build controls to avoid this.

What Schedule I‑1 Does And Why It Matters

Think of Schedule I‑1 as the CFC’s voice in your GILTI calculation. You gather gross tested income, allocable deductions, interest details, and QBAI at the entity level in functional currency. Those numbers then flow to Form 8992 so the U.S. shareholder can compute the inclusion. The instructions make this explicit, and they also explain which lines must be converted to U.S. dollars and at what rate.

A small but important update in the current instructions, Schedule I‑1 is completed once for the applicable separate category, and you indicate GEN or PAS at the top as needed. If there is passive category income on line 6, you include the PAS code. This helps you avoid duplicating the schedule when both general and passive tested income appear.

Downstream, Form 8992 picks up these I‑1 amounts. If you are a consolidated group, the group uses Schedule B of Form 8992 to relay each CFC’s I‑1 data to each member’s GILTI computation and to the consolidated computation. For non‑consolidated filers, Schedule A of Form 8992 does the same job.

Who Must File Schedule I‑1

If you are a Category 4 filer, you controlled the foreign corporation at any time in its annual accounting period, more than 50 percent by vote or value. If you are a Category 5 U.S. shareholder in the subcategory that reports GILTI, you also attach I‑1. Ownership tests include direct, indirect, and constructive attribution, so do not stop at the cap table. Walk the family and entity chains. You attach Form 5471, with I‑1 if required, to your federal return by that return’s due date, including extensions.

Quick Reference, Filer Triggers For I‑1

Filer category	Trigger	Typical I‑1 obligation
Category 4	You controlled the foreign corporation, more than 50 percent vote or value, during the year	Attach I‑1 with Form 5471
Category 5c or applicable 5 subcategory	You are a U.S. shareholder of a CFC on its last day and have GILTI items to report	Attach I‑1 with Form 5471

Confirm your category against the current instructions and remember, multiple categories can apply to the same person. The instructions detail when a single filer must complete multiple schedules without duplicating information.

What Goes On Schedule I‑1

At the CFC level, you will report, in functional currency, the pieces that determine tested income or tested loss, QBAI, and tested interest. The lines walk you from gross tested income to deductions and interest limits, then to QBAI and interest netting. Specific lines for interest, including 9a through 9d and 10a through 10c, are defined in the instructions, along with where average exchange rates apply for conversion to U.S. dollars (note that line 9d tested interest expense is floored at zero – if the formula yields a negative result, enter ‑0‑ rather than carrying a negative through to the shareholder).

Pro tip, do your tested income build in functional currency straight from a GAAP‑based income statement for the CFC, then perform required translations only where the instructions tell you to convert. That keeps tie‑outs clean and review time short.

How Schedule I‑1 Feeds Form 8992

Your I‑1 numbers are the inputs to the shareholder’s GILTI engine. Here is the simple mapping many teams post on their monitors during busy season.

Input from I‑1	How to think about it	Where it lands on 8992
Tested income and tested loss	Core driver of GILTI	Net tested income in Part I
QBAI	Basis for the 10 percent deemed return	Reduces GILTI base
Tested interest expense and income	Netting rules apply, affects tested income	Adjusts shareholder’s net tested income
Required translations	Average exchange rate where instructed	Dollar amounts on 8992 and schedules

If you are preparing the consolidated Schedule B for a group, the instructions lay out step‑by‑step how to total columns and when you can stop if losses offset income at the group level. That flow saves time when you manage dozens of CFCs.

Determining Filer Categories And Applicability

If you only remember one step before touching I‑1, make it this, confirm filer category. Everything else flows from that call. You start by deciding whether you are a U.S. shareholder with at least 10 percent vote or value, then you test whether the foreign corporation is a CFC, more than 50 percent owned by U.S. shareholders. The moment those two tests are true, Category 5 is on the table. If you controlled the corporation during its year, more than 50 percent by vote or value, Category 4 also applies.

Identify Filer Categories, Then Attach The Right Schedules

• Category 4, you controlled the CFC during its annual accounting period, attach Schedule I‑1.
• Category 5, you were a U.S. shareholder of a CFC on its last day and you have GILTI items, attach Schedule I‑1.
• Category 1, 2, and 3 can apply at the same time, but they do not, by themselves, trigger I‑1. Confirm all schedules for each category to avoid penalties.

Field note, we keep a single‑page ownership tree that shows direct, indirect, and constructive paths. Reviewers sign off on the tree before we finalize filer categories. That one page prevents most filing misses.

Apply Attribution Rules Carefully

Direct ownership is the easy part. Indirect and constructive ownership turn small percentages into filing triggers. Multiply indirect ownership through each entity tier, then add constructive ownership under family and related‑party rules. Remember that certain downward attribution rules may apply for Categories 1, 4, and 5, while Categories 2 and 3 often exclude them. Recheck the measurement on the last day of the CFC’s tax year, that date fixes Category 5 status.

Key Definitions You Will Use All Year

U.S. Person, U.S. Shareholder, CFC

• U.S. person, a U.S. citizen or resident, a domestic corporation or partnership, and certain domestic estates or trusts.
• U.S. shareholder, a U.S. person with 10 percent or more by vote or value, counting direct, indirect, and constructive ownership.
• CFC, foreign corporation where U.S. shareholders own more than 50 percent by vote or value, using those same attribution rules.

These three labels decide whether you attach I‑1. They also drive how you group income and taxes for foreign tax credit planning.

Functional Currency First, Dollar Translation Later

Schedule I‑1 is built on the CFC’s functional currency. That is by design. You compute gross tested income, allocable deductions, interest, and QBAI in functional currency, tied to a GAAP income statement. Only then do you translate specific lines into U.S. dollars for the shareholder’s Form 8992. This approach solves two problems. It keeps your CFC‑level workpapers clean for audit, and it reduces translation noise during review.

A Four‑Step Build That Keeps Reviews Short

• Identify the CFC’s functional currency and document the basis, especially if you changed it.
• Prepare a U.S. GAAP income statement in that functional currency, period‑matched to the CFC year that ends within your tax year.
• Compute tested income, tested loss, tested interest, and QBAI in functional currency. Track Section 163(j) adjustments at the CFC level.
• Translate where required for Form 8992. Keep the exchange rate workpaper with dates, rates, and sources. Tie it out once, lock it, and move on.

Reviewer tip, if a CFC is in a hyperinflationary economy, document the method you used and why it was appropriate for the period. Put that memo right behind the exchange rate printout so a reviewer can clear it in two minutes.

CFC‑Level GILTI Metrics You Report On I‑1

You will enter three big building blocks on Schedule I‑1, tested income or loss, QBAI, and tested interest. Each one has its own traps and controls.

Tested Income Or Loss

Start with gross tested income categories, then subtract allocable deductions. Remove amounts already picked up as Subpart F or related exceptions so you do not double count. Your line‑by‑line tie‑out to the GAAP income statement, in functional currency, is the audit shield. If you see an odd margin swing, chase it here before it hits 8992.

QBAI

QBAI is the average adjusted basis of qualified tangible property used in a trade or business to produce tested income. It exists to fund the 10 percent deemed return that reduces GILTI (note that QBAI of a CFC with a tested loss does not feed the deemed tangible income return – Schedule I‑1 line 9c isolates the tested loss QBAI amount so it does not improperly reduce tested interest expense). Track property additions, retirements, and depreciation methods. Put your basis rollforward right in the I‑1 binder and include a short note on capitalization policies so reviewers do not have to guess.

Tested Interest

Capture interest expense that is properly allocable to tested income and apply Section 163(j) at the CFC level when required. Net tested interest across entities at the shareholder level only after you have correct CFC inputs. If you miss an intercompany interest elimination or you mis‑bucket a related‑party loan, you will see it as a strange dip in QBAI and a jump in interest, a classic review slowdown.

Interaction With Foreign Tax Credits And Section 904

Schedule I‑1 does not carry the credit, but it drives it. Your tested income, QBAI, and tested interest from I‑1 set the base for the GILTI inclusion on Form 8992. That inclusion then flows into the foreign tax credit limitation under Section 904. If I‑1 is wrong, the limitation, the deemed paid credits, and any Section 250 deduction planning ripple the wrong way.

Simple Flow You Can Share With Your Team

• Build tested income or loss, QBAI, and tested interest at the CFC level on I‑1 in functional currency.
• Aggregate to U.S. dollars on Form 8992 and compute the GILTI inclusion.
• Apply Section 250 on Form 8993 if you are eligible.
• Map GILTI‑basket taxes in your credit model, then apply Section 904 limits (and note that, as of the Rev. 12‑2025 Form 5471, Schedule G line 20 now captures Pillar Two Top‑up Taxes – IIR, QDMTT, and UTPR – paid or accrued by the foreign corporation, which can affect the foreign tax credit and effective tax rate inputs that feed Schedule I‑1).
• Document any elections that affect basket placement and carryback or carryforward behavior.

Step	Input relies on	Output affects
I‑1 prep	Functional‑currency GAAP, interest limits, QBAI rollforward	Clean inputs to 8992
8992 calc	I‑1 tested items, translations, netting	GILTI inclusion amount
Credit model	Schedule E taxes, basket mapping, Section 960	Section 904 limitation

Reviewer cue, do not try to “fix” FTC math that looks off until you recheck I‑1. An overstated QBAI or a missed 163(j) adjustment is often the real culprit.

Coordination With Schedules H, J, P, And Q

Think of I‑1 as one cog in a set of gears. If the other gears skip, your numbers grind.

Schedule H, Current E&P

• Tie current E&P to the income statement that supports I‑1.
• Note timing differences that explain why E&P does not match tested income.
• Flag any Subpart F that should be out of the tested base.

Schedule J, Accumulated E&P

• Reconcile beginning and ending E&P in functional currency.
• Document translations so your I‑1 numbers still tie after currency effects.
• Keep a short memo on method and rates so reviewers clear it quickly.

Schedule P, PTEP

• Exclude previously taxed earnings from tested income.
• Label distributions that reduce PTEP so they do not drift into tested items.
• Keep a running PTEP ledger in the binder, one line per event.

Schedule Q, Income Groups

• Map income groups to tested versus non‑tested buckets.
• Align group‑level taxes and deductions with I‑1 totals to avoid leakage.
• Lock the mapping before you roll forward so imports do not overwrite.

Ownership Attribution Rules That Change Filing

Attribution determines who files and which schedules ride along. Start with the person that appears to own the shares. Then add indirect ownership through entities tier by tier. Layer on constructive ownership under family and related‑party rules. Recheck downward attribution where it applies. Finally, measure on the CFC’s last day to set Category 5 status, and test control during the year to set Category 4.

Quick audit proof, keep a one‑page tree that shows direct, indirect, and constructive percentages, with a date at the top. We put reviewer initials on that page before any returns are printed.

Common Errors And How To Avoid Them

Most I‑1 problems are preventable. Set controls before busy season, not during it.

Error pattern	What causes it	Preventive control
Missing I‑1 for a filer	Category misread, missed constructive ownership	Ownership tree, second‑person review of filer categories
FX swings that break tie‑outs	Early dollar translation, inconsistent rates	Build in functional currency, translate only where required, lock rate sheet
QBAI overstated	Basis rollforward gaps, missed retirements	Quarterly fixed asset rollforward tied to GL, reviewer checklist for retirements
Interest mis‑bucketed	Intercompany loans not eliminated, 163(j) missed	Intercompany matrix, 163(j) worksheet at CFC level, reviewer recalculation
Double counting income	Subpart F not removed from tested base	Subpart F reconciliation attached to I‑1, final reviewer sign‑off
Software overwrite	Imports overwrite reconciled fields	Freeze I‑1 after tie‑out, use a “do not import” flag before final compute
Late attachment	Extension assumed, not verified	Calendar with responsible owner, filing readiness meeting one week before deadline

A Quick Story From Review

We once saw a 14 percent swing in a client’s GILTI inclusion year over year. The cause was not a business change. It was a missed asset retirement that inflated QBAI in the prior year and a new intercompany note that pushed interest up in the current year. The fix was boring, a clean QBAI rollforward and an intercompany matrix. The result was great, two hours saved in every review for that group and no more surprises.

Functional‑Currency Documentation Package

Before you move to 8992, assemble a small packet that every reviewer expects.

• Functional currency memo with date of determination.
• GAAP income statement in functional currency, period matched.
• Exchange rate sheet with sources and dates.
• QBAI rollforward with additions, retirements, methods.
• 163(j) worksheet for the CFC.
• Subpart F and PTEP reconciliations, one page each.
• Ownership tree, dated and initialed.

If a reviewer can clear this packet in ten minutes, you have won half the battle with I‑1.

Timing, Due Dates, And Extensions

Attach Schedule I‑1 to Form 5471, then file the complete Form 5471 with the U.S. filer’s tax return by that return’s due date. If you validly extend the return, the extension generally carries to Form 5471 and its schedules. Align the CFC’s annual accounting period with the shareholder’s tax year that ends with or within your year, then lock your calendar so the team is not guessing near deadlines. If you are close to the date, schedule a readiness check one week prior to confirm all I‑1 tie‑outs, translations, and attachments are complete.

Getting The Latest Form And Instructions

Always pull the current form package and instructions from IRS.gov before you start. Confirm the revision date on both the Form 5471 instructions and the Form 8992 instructions. If your software has not rolled out the current schema, plan for an update window or prepare a paper attachment workflow. Keep a copy of the downloaded PDFs in your binder so reviewers can reference the exact revision you used.

Practical Filing Tips And A Ready‑To‑Use Checklist

Practical Tips

• Build from the CFC’s functional‑currency GAAP ledger and keep that ledger in the workpapers.
• Translate only where required and use one rate source across the file.
• Reconcile I‑1 to Schedules H, J, P, and Q before you touch Form 8992.
• Use a fixed asset rollforward template for QBAI and review it quarterly.
• Net tested interest only after you are comfortable with each CFC’s inputs.
• Lock fields in the software before the final compute step to avoid overwrite.
• Add a cover page that lists the person responsible for each tie‑out.

Documentation Checklist

• Category determination memo for each filer, with ownership tree.
• Functional currency memo and exchange rate sheet.
• GAAP income statement and trial balance in functional currency.
• Subpart F and PTEP reconciliations.
• QBAI rollforward and depreciation schedules.
• 163(j) computation at CFC level, with support.
• Form 8992 workpaper that shows how each I‑1 line maps.
• Final reviewer checklist with sign‑off and date.

Short Example To Ground The Steps

Let’s say your CFC reports 1,200 of gross tested income and 300 of allocable deductions in functional currency. Interest expense allocable to tested income is 40. Net tested income is 860. The CFC’s average QBAI is 2,500, so the 10 percent deemed return is 250. When this flows to 8992, that 250 reduces the base and the 40 of tested interest adjusts the net, before credits and any Section 250 deduction at the U.S. shareholder.

The exact math depends on your facts and elections. The point is workflow. Do it in functional currency, tie it once, translate where required, and your review flies.

When An Offshore Team Helps With I‑1

If your firm is strong on advisory but buried in international production, a disciplined offshore delivery model can stabilize capacity without giving up control. The key is structure, not resumes, standard workpapers, SOPs that match your 5471 flow, QBAI rollforwards, review ladders, and defined SLAs. This is the type of offshore work Accountably supports, U.S. led, security controlled, and built around review protection. Use it when you want predictable I‑1 packages that your reviewers can clear quickly.

Conclusion And Next Steps

Schedule I‑1 is not a mystery. It is a repeatable workflow. Build in functional currency, reconcile to Schedules H, J, P, and Q, then translate and map to Form 8992. Put a small packet on top of every file so reviewers clear it fast. If you want help building that packet at scale, with trained teams that work in your systems, reach out for a working session and we will walk your current binder, then propose a clean I‑1 architecture.

Common Mistakes We See Every Season

When I review a Schedule I-1 binder, the same problems repeat across CFCs and filers. Most are mechanical, easy to spot, and easy to prevent once the upstream workpaper chain is tight.

Reusable Checklists

These checklists are copy-paste ready. Drop them into your firm's SOP library and adapt the wording to match your engagement letter and review notes.

Keep Schedule I-1 (Form 5471) Season From Stalling

International tax season is its own slow grind. Schedule I-1 inputs alone require functional-currency math, conversion rates, and U.S. GAAP translation per CFC before the schedule ever feeds Form 8992 at the U.S. shareholder level. Per the Schedule I-1 instructions on IRS.gov, every numbered line carries three columns – Functional Currency, Conversion Rate, and U.S. Dollars – which is where most binders stall.

The form itself is not the bottleneck. The bottleneck is the upstream workpaper chain: functional-currency trial balance, exclusion tagging, FTC basket split, and reconciliation to Schedules H, J, P, and Q. Document that chain once, repeat it cleanly per CFC, and Schedule I-1 prep collapses from a week into a day.

• Standardize a CFC packet template that locks the three Schedule I-1 columns, the Separate Category code, and the parent Form 5471 attachment sequence (121) before any number is entered.
• Pull functional currency under U.S. GAAP first, log the conversion rate, and translate to U.S. dollars per the Schedule C translation rules. Never run the math the other way.
• Tag every gross-income stream as ECI (line 2a), subpart F (line 2b), high-tax exception under section 954(b)(4) (line 2c), related-party dividend (line 2d), or FOGEI (line 2e) before computing line 4.
• Hard-cap line 9d tested interest expense and line 10c tested interest income at zero in the workpaper formula so a negative result never flows to Form 8992.
• Prepare a separate Schedule I-1 per FTC basket when the CFC produces income in more than one separate category, and document the basket mapping for the reviewer.

That is the kind of structured execution our offshore tax delivery teams are built for: trained preparers, documented SOPs per schedule, multi-layer review, and turnaround SLAs that hold through the international filing window.

FAQs

Do I complete one Schedule I‑1 per CFC or per income basket?

You complete Schedule I‑1 at the CFC level and indicate the separate category at the top. If passive category items are present, mark PAS. This keeps baskets clear without duplicating schedules.

How do amended foreign financials affect I‑1?

If amended financials change the inputs used for tested income, tested loss, interest, or QBAI, you should assess whether an amended Form 5471 is required. Update I‑1, refresh the 8992 mapping, and retain a memo that explains materiality and timing.

Where should I handle 163(j) for GILTI, at the CFC or the shareholder?

Start at the CFC level so I‑1 reflects the right tested interest. Then, at the shareholder level, apply any required netting. Document both steps in the binder so a reviewer can trace the limitation.

How do disregarded entities roll into I‑1?

Treat disregarded entity activity as occurring inside the CFC. Include those transactions in the functional‑currency income statement and capture any intercompany eliminations or pricing adjustments before you build tested income.

What if a dividend is paid after year end, does it change PTEP on I‑1?

Usually, no. Post‑year‑end dividends do not retroactively change previously taxed earnings. Record the dividend in the period it is paid and manage PTEP ledgers and basis effects accordingly.