Best Time to Send Invoices for Payment [2026 Data]

The best time to send an invoice barely matters, at least by the hour. Omnisend’s 2026 analysis of roughly 26 billion email sends found only a 1.77-percentage-point gap between the single best hour-and-day combination, Sunday at 11 a.m. (33.69% open rate), and the single worst, Friday at 9 a.m. (31.92%). What moves the needle more is what the invoice says, and how fast a business follows up.

Why does invoice timing even matter right now?

Getting paid faster is worth real money, and the late payment statistics most invoicing data covers show that gap is closing. US small businesses were paid an average of 9.3 days late in the March 2025 quarter, and that window shortened every quarter after, down to 7.8 days late by December, the shortest in four years, per Xero’s Small Business Insights. Every business chasing that improvement wants an edge, which is why “send it at the right time” is worth a real data check rather than another recycled claim.

Figure 1: Average days a US invoice runs late, by quarter. Source: Xero Small Business Insights, US, December 2025 quarter.

Does the hour you send an invoice actually change anything?

Barely, and that is worth stating plainly before diving into the numbers, because plenty of invoicing advice online implies the opposite: that missing some magic window costs a business real time on the calendar. It doesn’t, at least not by more than a rounding error. Most invoices today go out as an email or an emailed link, so the closest real proxy for “does timing matter” is what email engagement research actually measures at scale, across billions of sends rather than one person’s anecdote.

Omnisend tracked roughly 26 billion email sends for its 2026 report and broke out each day’s single best-performing hour for opens. Sunday at 11 a.m. led at 33.69%, followed closely by Tuesday at 7 a.m. (33.41%) and Saturday at 9 a.m. (33.19%); Thursday’s best slot, 2 p.m., reached 33.06%, and Monday’s, 1 p.m., reached 32.68%. The floor was Friday at 9 a.m., 31.92%, still within two percentage points of the week’s ceiling. That is a narrow enough band that picking any one of these hours over another buys almost nothing measurable.

Figure 2: Peak open rate at each day’s single best hour, 2026. Source: Omnisend, The Best Time to Send an Email (2026), roughly 26 billion emails analyzed.

A separate HubSpot survey of more than 150 US marketing professionals lands on a related but distinct answer: opinion, not open-rate logs. 27% named Tuesday their best-performing day, ahead of Monday (19%) and Thursday (17%), and most reported peak engagement between 9 a.m. and noon or between noon and 3 p.m., a window that overlaps comfortably with Omnisend’s actual peak hours without pinning down one exact minute. The honest read across both data sources: a late-morning-to-early-afternoon weekday send captures nearly all of the available advantage, and chasing the single best-performing hour past that point is optimizing a rounding error.

How fast does an invoice actually get opened after you hit send?

Faster than the hour-of-day debate suggests, and mostly independent of which hour was chosen. GetResponse’s benchmark report, drawn from 4.4 billion messages its customers sent, tracked the exact hours between send and open across that entire dataset: 21.2% of all opens happened in the first hour, another 7.44% in the second hour, and by the 5-hour mark, 44.24% of everything that would ever be opened already had been. By hour 10, that cumulative share reached 55.17%.

Figure 3: Cumulative share of email opens, by hours after sending. Source: GetResponse, Email Marketing Benchmarks report, 4.4 billion messages sent by GetResponse customers in 2023.

The practical read is simpler than a best-hour lookup table: most of an invoice’s visibility gets decided in the same business day it’s sent, regardless of the exact hour, because recipients who are going to open an email tend to do it soon after it lands in an active inbox. A send that misses that window entirely, like one that lands well outside business hours in the recipient’s time zone, loses more from the delay until the next active inbox check than any single business hour would cost against another.

If timing barely moves the needle, what actually gets an invoice paid faster?

Wording does, by a much wider margin than send time ever will. FreshBooks scanned payment terms across more than 1 million small-business invoices and tracked, for each stated term length, what share of invoices got paid within a fixed 7-day window: invoices marked “7 Days” hit that mark 58.05% of the time, versus 52.84% for “14 Days” and just 40.22% for “30 Days,” even though the 30-day group technically had three weeks more room to pay. Shorter, more specific terms don’t just set an earlier due date; they appear to change how the customer prioritizes the invoice against everything else in their queue.

Figure 4: Share of invoices paid within 7 days, by stated payment term. Source: FreshBooks, invoice payment-terms data (1M+ invoices analyzed).

That gap, nearly 18 percentage points between the best and worst term length, dwarfs anything the send-time data could produce. It also suggests the mechanism isn’t really about the calendar date the customer technically owes money by; it’s about how the invoice gets sorted into “handle now” versus “handle eventually” the moment it lands, and a short, specific term reads as more urgent than a vague, distant one even before the recipient does the math on the actual due date.

Tone matters too, and it costs nothing to add. The same FreshBooks dataset found invoices that included the phrase “Thank You” in their payment terms were paid 89.61% of the time, edging out “Please” at 88.07%. Neither difference is enormous on its own, but stacked against a send-time advantage worth well under 2 percentage points, wording is doing measurably more work. A related question worth asking alongside “when” is “how often”: the single most reliable lever isn’t the first send at all, but whether a consistent reminder cadence follows it when the invoice goes unpaid past its due date.

Figure 5: Invoices paid when the payment terms read “Thank You,” 2026. Source: FreshBooks, invoice payment-terms data (1M+ invoices analyzed).

Send Timing at a Glance

Timing or wording signal	What the data shows	Source
Best hour-and-day for opens	Sunday, 11 a.m.: 33.69% open rate (vs. 31.92% low, Friday 9 a.m.)	Omnisend, 2026
Speed of engagement after sending	21.2% of opens land in the first hour; 44.24% within 5 hours	GetResponse, 2024 report
Payment-term wording	Within 7 days of sending: 58.05% of “7-Day” term invoices paid (vs. 40.22% for “30-Day” terms)	FreshBooks
”Thank You” wording	89.61% of invoices paid (vs. 88.07% for “Please”)	FreshBooks
US late-payment trend	7.8 days late, December 2025 quarter (down from 9.3 days, March 2025)	Xero Small Business Insights

Table 1: Every send-timing and wording lever with a real dataset behind it, compared side by side. The gap between the best and worst send-time slot is under 2 percentage points; the gap between the best and worst payment-term wording is nearly 18 points.

The Bottom Line

Chasing the single best hour to send an invoice is optimizing a lever that barely moves: Omnisend’s 26-billion-email dataset puts under 2 percentage points between the best and worst slot in the week, and most of that theoretical advantage disappears anyway once you account for how fast people actually check their inbox after a send lands. The levers that do move payment speed by a meaningful margin are the ones on the invoice itself, shorter stated terms and a courteous line, plus what happens after the first send if it goes unanswered. BillyPaid’s payment reminders handle that second half automatically, running a consistent follow-up cadence on every invoice so a slow payer gets a nudge without anyone having to remember which day of the week they last checked.

Frequently Asked Questions

What is the best time of day to send an invoice? By email engagement data, late morning to early afternoon on a weekday. Omnisend’s 2026 analysis of roughly 26 billion email sends found the single best hour-and-day combination was Sunday at 11 a.m. (33.69% open rate), but every weekday clusters within about 1.5 percentage points of that peak when you use each day’s own best hour, so there is no one dramatically superior slot. HubSpot’s survey of over 150 US marketers points to the same broad window, with most reporting peak engagement between 9 a.m. and noon or noon and 3 p.m.

What day of the week should I send an invoice? Any weekday works about as well as any other. Omnisend’s 2026 data puts Sunday’s peak hour narrowly ahead at 33.69%, followed by Tuesday at 33.41% and Saturday at 33.19%, with Friday lowest at 31.92% at its own best hour, a spread of under 2 percentage points across all seven days. A HubSpot survey of marketers still shows a preference: 27% named Tuesday as their best-performing day, ahead of Monday (19%) and Thursday (17%).

Does sending an invoice at a certain time actually get it paid faster? Less than the wording on the invoice does. GetResponse’s analysis of 4.4 billion messages found 21.2% of all email opens happen within the first hour after sending and 44.24% happen within 5 hours, regardless of what hour that send happened to land in, so most of an invoice’s visibility is set by how fast someone checks their inbox, not by the sender’s chosen minute. FreshBooks’ analysis of more than 1 million invoices found a much bigger lever: measured within a fixed 7-day window after sending, invoices with a stated 7-day term are paid 58.05% of the time, versus just 40.22% for invoices with a 30-day term, even though the 30-day group technically had three weeks more room to pay.

Is invoice payment speed actually improving? In the US, yes. The average invoice ran 7.8 days late in the December 2025 quarter, the shortest late-payment window in four years and a full day inside the 8.8-day long-run average, down from 9.3 days late in the March 2025 quarter, according to Xero’s Small Business Insights.

Sources and References

1. Omnisend: The Best Time to Send an Email (2026 Research), roughly 26 billion emails analyzed, day-and-hour open rate breakdown.
2. GetResponse: Email Marketing Benchmarks report, 4.4 billion messages sent by GetResponse customers in 2023, cumulative opens by hour after sending.
3. HubSpot: The Best Time to Send an Email, survey of over 150 US marketing and advertising professionals, updated July 2026.
4. FreshBooks: invoice payment-terms data (1M+ invoices analyzed), payment-term length and “Thank You” wording effect on payment speed.
5. Xero: Small Business Insights, US, December 2025 quarter, quarterly late-payment days data.

Note: All figures verified as of September 2026.