The State of Solar Supply Chain Payments

Across 1,337 fully repaid invoices, 67% were paid after the seller's terms window closed — 70% of the dollar volume. The median buyer who went past terms took 58 additional days. One in ten took 120 days or more.

Read that carefully before calling it late payment. Every one of these invoices was paid in full. These buyers were on a platform built to let them extend — the extension carries a fee, the supplier is already paid, and nobody is chasing a check. What this number measures is demand for time: when the penalty for taking longer is a known fee instead of a damaged relationship, two-thirds of solar buyers take longer.

Suppliers offering terms out of their own pocket should sit with that. The demand for 60, 90, 120 days exists in your customer base whether you can see it or not. What varies is who absorbs it.

The clearest pattern in four years of data: wherever buyers had room, they used about three months.

• Buyers who financed a purchase from day one took a median of 96–109 days to pay, depending on year.
• Buyers on NET-60 terms took a median of 74–103 days.
• Only buyers on NET-30 cluster near 30 days — and they self-select: buyers who know they can pay fast choose short terms.

The median across all repaid invoices is 68 days. The industry's default invoice term is 30. That mismatch isn't buyer misbehavior — it's project structure. Solar projects pay on milestones, retainage, incentive timing, and utility interconnection schedules. The money that pays a distributor's invoice often hasn't reached the installer when day 30 arrives.

Invoices coming due in September and October were extended 75–82% of the time. The median invoice due in October was paid roughly 60 days past its terms. The median invoice due in May was paid 2 days past.

That's not a rounding difference — it's a different market depending on the calendar. The pattern is consistent with how the install season and incentive cycle move cash: Q4 completion pushes, year-end interconnection queues, and tax-credit timing that pulls project cash into the new year. (Our data shows the payment pattern; the causes are industry context, not something an invoice ledger can prove.)

For a supplier, the practical version: receivables coming due in the fall will run long. Price it, plan it, or transfer it.

Holding terms constant to remove mix effects, buyers on NET-30 terms took a median of 56 days to pay in 2023 and 42 in 2024 — then 29 days in 2025 and 2026, with the share going past terms falling from 60% to roughly a third. Volume-weighted, average days-to-pay across the book peaked at 106 days in 2024, easing to 73 in 2025 and 63 so far in 2026 (partial year, and recent figures will drift up slightly as open invoices resolve).

The peak years line up with the industry's hardest stretch in a decade — the rate environment, module price collapse, and residential demand shock. The data says discipline returned in 2025 for buyers on short terms. It says something different about buyers on long terms:

While NET-30 buyers normalized, buyers on NET-60 terms went the other way: the share paying past terms rose from 67% in 2023 to 83% in 2026, and their median total payment cycle stretched from 74 to 103 days.

This is selection, not deterioration. Buyers who know their projects pay slowly choose longer terms, and then use them fully. The two groups aren't the same buyers behaving differently — they're different buyers telling you who they are by the terms they pick. For anyone underwriting or extending trade credit in solar, the terms a buyer requests are themselves a signal.

82% of repaid invoices were settled in a single payment. Only 3% took three or more installments. Solar buyers don't trickle money in as it arrives — they wait for the project milestone that funds them, then clear the invoice whole.

This matches everything above: the constraint isn't willingness or solvency, it's when the project pays. Once it does, the invoice clears same-week.

Source. Anonymized transaction records from the Yellowpay platform: trade credit applications and funded trade invoices from April 2022 through August 2026. Payment-timing statistics use the 1,337 invoices fully repaid by the data cutoff.

A point in time, not a running total. Every figure here is a cut at the August 2026 data cutoff, frozen at publication. The platform has continued funding invoices since; this analysis does not follow it, because a published finding should keep describing the sample it was computed from.

The selection frame, stated plainly. These are invoices financed on a platform that pays the supplier within 2 business days and allows the buyer to extend payment up to 120 days for a known weekly fee. That is a strength and a limit: it reveals what buyers do when extending is a priced option rather than a broken promise — but it is not a random sample of all solar trade. Buyers and suppliers who use trade credit platforms may differ from those who don't.

Definitions. "Terms" are the days the supplier covered for the buyer. An invoice counts as extended if full repayment landed after the covered window (fees begin the day after the original due date). Days-to-pay runs from purchase date to full repayment. "Repeat suppliers" funded two or more invoices; their average of 21 invoices is 17 excluding our largest supplier.

Exclusions and caveats. Cancelled and refused applications are excluded from all figures. Defaulted invoices are excluded from payment-timing statistics. 2022 data (April onward, small early sample) is included in totals but trend commentary starts in 2023. 2026 covers January through early August; because slow-paying invoices from recent months are still open, recent-cohort timing figures are provisional and will drift modestly upward. No statistic is published for any segment smaller than five suppliers.

What we don't publish. Individual company data, loss rates, and pricing outcomes. Aggregates only.

How long do solar buyers actually take to pay invoices?

The median across 1,337 repaid trade invoices was 68 days. When buyers had meaningful runway — 60-day terms or day-one financing — the median payment cycle was roughly 90–100 days.

Do buyers actually use extended payment terms when offered?

Yes. 67% of invoices were paid after the supplier's terms window ended, with a median extension of 58 days. One in ten buyers who extended took 120 days or more.

Is that late payment?

No. Every invoice in the payment-timing analysis was paid in full, on a platform where extending carries a known fee and the supplier has already been paid. It measures how much time buyers take when time is a priced option.

When is payment slowest in the solar supply chain?

Invoices due in September and October were extended 75–82% of the time, with median payments about 60 days past terms. Invoices due in May and June were extended barely half the time, with median payments 2 days past terms.

Where does this data come from?

Anonymized, aggregated transaction records from the Yellowpay platform: solar trade invoices funded in the US between April 2022 and the August 2026 data cutoff. Payment-timing figures use the 1,337 invoices fully repaid by that cutoff.

Will this report be updated?

Yes — annually, with the underlying book re-verified quarterly.