FL-150: "last month" versus "average monthly"
Published October 27, 2026
Item 5 of California's Income and Expense Declaration, form FL-150, asks for each kind of income twice: once in a column headed "Last month" and once in a column headed "Average monthly". The two numbers are often different, and that is expected. This guide explains what the form says about each column and works through an example. It is general information, not legal advice.
What the form says
The heading of item 5 reads: "Income (For average monthly, add up all the income you received in each category in the last 12 months and divide the total by 12.)" Below it are the income lines, from 5a "Salary or wages (gross, before taxes)" through 5l "Other (military allowances, royalty payments)", each with both columns.
- Average monthly has a method on the form: the last 12 months of that kind of income, added up and divided by 12.
- Last month has no further instruction on the form. It is one month's figure for the same line, and the form does not define which calendar month it means. If that matters for the date you sign, the court's self-help center can tell you how it is usually read.
Other items use only one of the two columns. Item 10, deductions, has only a "Last month" column. Item 13, expenses, is headed "Average monthly expenses" and has no "Last month" column at all.
A worked example: a raise during the year
Suppose gross pay was $4,600 a month from October 2025 through April 2026, and $5,000 a month from May through September 2026, with overtime paid on top in some months.
| Month | 5a Salary (gross) | 5b Overtime (gross) |
|---|---|---|
| October 2025 | $4,600.00 | $0.00 |
| November 2025 | $4,600.00 | $180.00 |
| December 2025 | $4,600.00 | $247.50 |
| January 2026 | $4,600.00 | $0.00 |
| February 2026 | $4,600.00 | $412.50 |
| March 2026 | $4,600.00 | $330.00 |
| April 2026 | $4,600.00 | $0.00 |
| May 2026 | $5,000.00 | $165.00 |
| June 2026 | $5,000.00 | $495.00 |
| July 2026 | $5,000.00 | $247.50 |
| August 2026 | $5,000.00 | $82.50 |
| September 2026 | $5,000.00 | $412.50 |
| Total, 12 months | $57,200.00 | $2,572.50 |
| Average monthly (total ÷ 12) | $4,766.67 | $214.38 |
| Last month (September 2026) | $5,000.00 | $412.50 |
The two columns tell different things. "Last month" shows the current rate. "Average monthly" shows the year. Here the average salary is lower than last month because of the raise, and last month's overtime is nearly double the average because overtime varies.
Where the figures come from
Lines 5a and 5b ask for gross amounts, before taxes. Pay stubs show gross pay; your bank deposits show net pay, after taxes and deductions. The form asks you to attach pay stubs for the last two months. For income that is not on a pay stub, such as support received, rental income or commissions paid separately, bank statements are often the record of each month. See FL-150 monthly averages from bank statements for the full walk-through.
When the year was not typical
The form has two places for a year that does not look like the next one:
- Item 8, additional income: "I received one-time money (lottery winnings, inheritance, etc.) in the last 12 months (specify source and amount)".
- Item 9, change in income: "My financial situation has changed significantly over the last 12 months because (specify)".
The form does not tell you to leave months out of the average when your income changed. What to write in items 8 and 9, and how to present a change, are decisions for you, ideally with a lawyer or the self-help center. For bonuses, commissions and gig income, see irregular income on a financial affidavit.
Keep both numbers traceable
Whichever month you use for "Last month", note it. Whichever 12 months you averaged, note them too. You sign the FL-150 under penalty of perjury, and a short note of the months behind each figure makes a question about it easy to answer.
Financial Affidavit Numbers shows both columns for each item 5 line it finds in your statements: the most recent month and the 12-month average, with the deposits behind each. It flags one-off deposits for you to decide on, and it does not fill in the FL-150; you copy the numbers onto the form.
Common questions
What does 'last month' mean on the FL-150?
It is the column in item 5 for one month's income on each line, next to the 12-month average. The form gives no further definition. If it matters for the date you sign, ask your court's self-help center how it is usually read.
How is average monthly income calculated on the FL-150?
Item 5 says: add up all the income you received in each category in the last 12 months and divide the total by 12. Do it per line, using gross amounts for wages and overtime.
What if my income changed during the year?
The 12-month average still covers the whole year. Item 9 of the FL-150 is where the form asks you to say if your financial situation changed significantly over the last 12 months, and why. How to present it is your decision.
Does the FL-150 expense section have a last month column?
No. Item 13 is 'Average monthly expenses' only. Item 10, deductions, is the reverse: it has only a 'Last month' column.
Turn your bank and card statements into monthly figures by form line →More guides: FL-150 monthly averages from bank statements · How many bank statements for the FL-150 · FL-150 item 13, line by line · FL-150 vs FL-142 · When the FL-150 is filed or served · Florida short form vs long form · Florida: weekly and biweekly to monthly · Florida financial affidavit, section by section · Florida financial affidavit deadline · Credit card payments vs purchases · Transfers between your own accounts · Irregular income on a financial affidavit · Financial affidavit tools compared · A financial affidavit in a spreadsheet