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Days between two dates in Excel

Each invoice has a due date and the date it was paid. In D2:D7, work out how many days late each payment was. Paid on the due date is 0 days late; paid early shows as a negative number.

Excel stores a date as a number: the days since 1/1/1900. So one date minus another gives the days between them. Take the due date away from the paid date.

51 How many days late? Date arithmetic Core

invoices.xlsx
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Click a cell while typing to insert it, drag to select a range, F4 adds $, Esc cancels.

Tap a cell while writing a formula to insert it, or slide across cells for a range. The strip above the keyboard has = ( ) : , $.

The Date arithmetic guide

A date in Excel is a number of days, so =C2-B2 gives the days from B2 to C2. Paid date minus due date is how many days late a payment was: 0 on the due date, negative when it was early.

CoreAbout 3 minutesBy Updated

Dates are numbers

Excel counts days from 1 January 1900. 3/9/2026 is stored as 46090 and shown as a date because of the cell's format. That is why subtracting works: 3/9/2026 minus 3/2/2026 is 7.

Which way round

Later date minus earlier date gives a positive number. For days late, that is paid - due. A payment made before the due date gives a negative number, which is the honest answer: it was early. If the report should show 0 for those, use =MAX(0, C2-B2), as in the aging challenge.

Other ways to write it

Calendar days or working days?

Payment terms count calendar days, weekends included. NETWORKDAYS(B2, C2) counts Monday to Friday and includes both ends, which answers a different question. The month-end challenge uses it.

Common mistakes

FAQ

How do I calculate the days between two dates in Excel?
Subtract them: =C2-B2, later date first. =DAYS(C2,B2) does the same.
Why does my date subtraction show a date instead of a number?
The answer cell has a date format. Set it to General or Number and the days show.
Why does DATEDIF return #NUM!?
DATEDIF needs the earlier date first. When the start date is later than the end date, it returns #NUM! instead of a negative number.
Should I count working days or calendar days for late payments?
Usually calendar days: payment terms such as 30 days include weekends. NETWORKDAYS counts Monday to Friday only.

All challenges

  1. 01Starter, 3 min Add it upSUM
  2. 02Starter, 3 min Find the averageAVERAGE
  3. 03Starter, 3 min Smallest and largestMIN, MAX
  4. 04Starter, 3 min Count what's thereCOUNT, COUNTA, COUNTBLANK
  5. 05Starter, 3 min Write once, fill downRelative references
  6. 06Core, 3 min Lock it with $Absolute references
  7. 07Starter, 3 min Percent of a totalPercentages
  8. 08Starter, 3 min Make the numbers readableNumber formats
  9. 09Core, 3 min Up or down by how much?Percent change
  10. 10Core, 3 min What you see vs what's storedROUND
  11. 11Core, 3 min The typical valueMEDIAN
  12. 12Core, 3 min Select to the end in one moveCtrl + Shift + arrow
  13. 13Starter, 3 min Sort without breaking rowsSort
  14. 14Starter, 3 min Filter to what mattersFilter
  15. 15Starter, 3 min Copy and paste a formulaCtrl+C, Ctrl+V
  16. 16Core, 3 min Paste values onlyPaste Special → Values
  17. 17Core, 3 min Highlight what's over targetConditional formatting
  18. 18Core, 3 min Spot the duplicatesDuplicate Values rule
  19. 19Core, 3 min Pass or fail?IF
  20. 20Core, 3 min Both or either?AND, OR
  21. 21Core, 3 min Exactly one of the twoXOR
  22. 22Core, 3 min Grade bands with nested IFNested IF
  23. 23Core, 3 min Count the ones that matchCOUNTIF
  24. 24Core, 3 min Add up the ones that matchSUMIF
  25. 25Core, 3 min Use a cell as the conditionCriteria in a cell
  26. 26Core, 3 min Partial matches with * and ?SUMIF, COUNTIF with wildcards
  27. 27Core, 3 min Count with two conditionsCOUNTIFS
  28. 28Core, 3 min Add up with two conditionsSUMIFS
  29. 29Core, 3 min Look it upVLOOKUP
  30. 30Core, 3 min Find the right bracketVLOOKUP approximate match
  31. 31Core, 3 min XLOOKUP, the modern wayXLOOKUP
  32. 32Core, 3 min Where is it in the list?MATCH
  33. 33Advanced, 3 min INDEX and MATCH togetherINDEX + MATCH
  34. 34Advanced, 3 min Lock just the row or the columnMixed references
  35. 35Advanced, 3 min Growth per year (CAGR)CAGR with ^
  36. 36Core, 3 min Use a rate from another sheetReferences to other sheets
  37. 37Core, 3 min Catch the error, not the bugIFERROR
  38. 38Core, 3 min Which invoices are missing?Compare two lists
  39. 39Core, 3 min Reconcile the ledger with the bankXLOOKUP or VLOOKUP + IFNA
  40. 40Core, 3 min Join text together&, CONCAT, PROPER
  41. 41Core, 3 min Split first and last namesLEFT, MID + FIND
  42. 42Core, 3 min Stray spaces that break a countTRIM
  43. 43Core, 3 min Flag the bad entriesTRIM, LEN, EXACT
  44. 44Advanced, 3 min Clean a bank descriptionTEXTBEFORE, TEXTAFTER, PROPER
  45. 45Core, 3 min Mistake hunt: #N/A everywhereFixing #N/A
  46. 46Core, 3 min Mistake hunt: hard-coded numbersReferences instead of typed numbers
  47. 47Core, 3 min Mistake hunt: numbers stored as textNumbers stored as text
  48. 48Core, 3 min One of each, then the totalsUNIQUE
  49. 49Core, 3 min Your first pivot tablePivot tables
  50. 50Advanced, 3 min Which category went up most?SUMIFS, change, lookup
  51. 51Core, 3 min How many days late?Date arithmetic
  52. 52Core, 3 min Turn text into real datesDATEVALUE
  53. 53Advanced, 3 min Month ends and working daysEOMONTH, NETWORKDAYS
  54. 54Core, 3 min Renewal datesEDATE
  55. 55Core, 3 min Days overdue and aging bandsDate difference, aging bands
  56. 56Core, 3 min How many late orders?Pick the tool
  57. 57Core, 3 min Sales per repPick the tool
  58. 58Core, 3 min Whose part is it?Pick the tool
  59. 59Core, 3 min Who gets the bonus?Pick the tool
  60. 60Core, 3 min Each region's sharePick the tool
  61. 61Advanced, 3 min Case: the supplier reportCase, five steps
  62. 62Advanced, 3 min Case: the monthly budgetCase, five steps
  63. 63Advanced, 3 min Case: the reorder listCase, five steps

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