3 Excel Formulas to Track Warranty Expirations, Household Budgets and Birthdays

All three formulas use Excel tables, so the examples refer to table names such as T_Receipts and T_Budget. You can rename these to match your own workbook, but the column names have to match too.

Formula 1: Find warranties expiring in a given month​

Goal: Type a month name and a year, and get a live list of every receipt whose warranty ends then.

Setup assumed in the example:

• A table named T_Receipts with a Warranty column of real Excel dates.
• A month name (for example, "January") in G2 and a year in G3.
• The formula goes in F6, with clear cells to the right and below it.

=FILTER(T_Receipts,(MONTH(T_Receipts[Warranty])=MONTH(DATEVALUE(G2&"1")))*(YEAR(T_Receipts[Warranty])=G3),"No items")

How it works:

• DATEVALUE converts a date stored as text into a serial number that Excel recognizes as a date. The formula glues "1" onto the month name, so "January" becomes a string like "January1". DATEVALUE turns that into a date, and MONTH extracts the month number.
• Each row's warranty date is reduced to a month number and compared with that target. A second test does the same for the year against G3.
• Multiplying the two tests means a row survives only when both are TRUE. Microsoft's own FILTER documentation uses the same pattern, where the multiplication operator returns rows that meet condition A AND condition B.
• The last argument, "No items", is the fallback. Microsoft notes that without it, an empty result produces a #CALC! error because Excel doesn't currently support empty arrays.

Why a table helps: Microsoft says that if your data is in an Excel table and you use structured references, the spilled array resizes as you add or remove rows. New receipts show up without you editing the formula.

Common failure points:

• Text "dates." If a warranty entry is stored as text, MONTH and YEAR will misbehave or return errors. Make sure the column holds real dates.
• Month parsing. Microsoft cautions that a computer's system date settings can change DATEVALUE results. A month name plus "1" may not parse the same way under every regional setup. If it returns #VALUE!, check the entry in G2 and your locale. The drop-down list in the original advice reduces typos, but it can't guarantee parsing on every system.
• Blocked spill. If anything sits in the cells the results need, Excel can't display the full list. Clear the area.
• Results show as numbers. Excel stores dates as serial numbers. Format the output date column as Date.
• No reminders. The formula lists matches. It doesn't notify you, and it doesn't know your warranty terms.

Version note: Microsoft's FILTER page lists Microsoft 365, Excel 2024, Excel 2021 and the mobile apps. It doesn't list Excel 2019 or 2016.

Formula 2: Grade each budget category​

Goal: Label each category "Within budget," "Near budget," "Budget hit," or "Over budget."

Setup assumed in the example:

• A table named T_Budget with Category and Cost columns.
• The category name in E2 and its limit in F2.
• The formula in G2, filled down to G8.

=LET(Spend,SUMIF(T_Budget[Category],E2,T_Budget[Cost]),IFS(Spend>F2,"Over budget",Spend=F2,"Budget hit",Spend>(F2*0.9),"Near budget",TRUE,"Within budget"))

How it works:

• SUMIF adds up every cost whose category matches E2.
• LET stores that total under the name Spend. Microsoft describes LET as assigning names to calculation results, and says it can make formulas easier to read and avoid recalculating repeated expressions.
• IFS then checks conditions in order and returns the result for the first TRUE one. Microsoft says a final TRUE acts as the default, which is how "Within budget" works here.

The thresholds, spelled out:

Edge cases to know:

• Exactly 90% of the limit counts as "Within budget," because the test is strictly greater than.
• "Budget hit" needs exact equality. With decimal amounts, expect it to be rare.
• A category in E2 that doesn't exist in the table sums to zero, so it usually reads "Within budget."
• Category labels must be spelled consistently, or SUMIF will split your spending across lookalike names.
• The original walkthrough has a stray fragment that reads like SpendNow. The working formula names the variable Spend, so use that.
• Despite the "monthly" framing, the formula as written sums every row in the table for that category. To get a monthly view, you'd need to keep one month of data in the table or add a date condition. That's an extension of the formula, not part of it.

Version note: Microsoft lists LET for Microsoft 365, Excel 2024 and Excel 2021, with their Mac equivalents. IFS also covers Excel 2019. So this formula needs a newer Excel than 2019 because of LET.

Formula 3: Days until the next birthday​

Goal: A Days column that counts down to each person's next birthday.

Setup assumed in the example: A table with a Birthday column of real dates, and the formula entered in the Days column. In a table, it fills down on its own.

=IF(DATE(YEAR(TODAY()),MONTH([@Birthday]),DAY([@Birthday]))<TODAY(),DATE(YEAR(TODAY())+1,MONTH([@Birthday]),DAY([@Birthday])),DATE(YEAR(TODAY()),MONTH([@Birthday]),DAY([@Birthday])))-TODAY()

How it works:

1. It rebuilds this year's birthday from the stored month and day.
2. If that date is earlier than today, it rebuilds it for next year instead.
3. It subtracts today's date. Excel dates are serial numbers, so the difference is a day count.

What you'll see:

• A birthday today returns 0, because the test uses "less than" and today isn't earlier than today.
• If the result appears as a date, change the cell format from Date to Number.
• TODAY updates when the workbook recalculates, so the countdown stays current each time you open it.

The leap-day catch: Microsoft's DATE documentation says a day value larger than the month's length rolls into the following month. A February 29 birthday in a non-leap year will therefore land in March rather than on February 28. The formula doesn't choose a leap-day policy. If you have a leap-day person on your list, decide whether you celebrate February 28 or March 1 and handle that row separately.

Compatibility at a glance​

If you're on Excel 2019 or earlier, the birthday formula is the safe one to start with.

Verdict​

These are good household formulas because each does one job and none of them tries to be clever for its own sake. The caveats are mostly about data hygiene. Use real dates, keep category names consistent, and leave room for spills. The author's description of these as life-changing is personal framing, and I can't verify it. The formulas themselves hold up against Microsoft's documentation.

I couldn't see the author's screenshots or workbook, so the layouts above come from the described setup rather than a file I inspected. Test each formula on a few dummy rows before you trust it with your warranty claims.