Want to access all premium content?
Become a paying subscriber to get access to all courses, guides like this, prompts and skills library, and $500+ worth of AI tools.
A bank statement shows what you paid. It takes a closer look to notice that your internet bill went up, a merchant charged you twice, or card interest has been climbing month after month.
In this guide, you’ll give Claude six months of bank and card transactions and ask it to calculate the totals with code. You’ll see where your money went, which charges deserve a closer look, and the original rows behind each figure. To follow along, you’ll need a Claude account and a CSV export from your bank or the demo files in the kit. The workflow uses exported files, so there’s no bank connection to set up.
Step 1: Export your statements. Download six months of bank and card transactions.
Step 2: Set up a Money Audit Project. Save your currency, paydays, and spending rules.
Step 3: Map where it went. See fixed bills, flexible spending, and income by month.
Step 4: Find the leaks. Look for fees, interest, possible duplicates, and price increases.
Step 5: Check the numbers. Trace any total back to its transactions.
Step 1: Export your statements
In your bank’s website or app, look for Statements, Download, or Export. Choose CSV and select the last six months. Repeat this for each credit card you want to include.
Open each file in Google Sheets, Excel, or a text editor. Keep the column headers and transaction rows. Remove any account numbers, names, and addresses before saving a copy to upload.
If your bank offers only PDFs, Claude can read those too. This walkthrough uses CSV because you can compare its calculations directly with the transaction rows.
To practice first, use demo-checking.csv and demo-credit-card.csv from the kit. They contain fictional transactions from May through October 2026, including fees, price increases, and a duplicate charge.
Step 2: Set up a Money Audit Project
Open Projects in Claude’s sidebar and select New project. Enter Money Audit in the project name field and create the project.
Select Set project instructions and paste the following. Change the currency and paydays to match yours, then save.
You're my money auditor. I'll upload bank and card statements as CSV files. Use code for every calculation and never estimate a total. Treat the latest full month in my files as "this month". My currency is USD. My paydays are the 15th and the last working day of each month. Card purchases count as spending. Card payments and transfers between my own accounts are not spending or income. Fixed bills are rent, utilities, phone, internet and insurance. All other spending is flexible. Show amounts to the cent, and be ready to list the transactions behind any number. If you're unsure about a row, flag it instead of guessing.
The transfer rule matters when you upload both checking and card files. Your card purchases count when they appear on the card statement. Paying that bill from checking is money moving between accounts you own.
If Claude says it can’t run code, open Settings, then Capabilities, and check that Code execution and file creation is enabled.
Step 3: Map where it went
Start a chat inside Money Audit and attach the CSVs using the + button. Keep the files attached to this chat so later audits can use their own statements.
Where did my money go this month? Split my fixed bills from my flexible spending. Then show a table with fixed, flexible, total spending and income for every month in the files.
Look for one row per month and a list of any transactions Claude excluded or flagged. In the demo, October shows $1,764.30 in fixed bills, $1,272.52 in flexible spending, and $3,380 in income.
The $450 card payments and August’s $1,500 transfer from savings should stay out of spending and income. Check any month that looks unusual. August’s $5,619.19 in spending, for instance, includes a $2,400 car repair.
If a month looks incomplete or a total seems off, ask Claude to show the rows it used.
Step 4: Find the leaks
In the same chat, ask Claude to look through every account you uploaded.
Check every account in these files for fees, interest, charges that hit twice, bills that went up and subscriptions. Put them in one table with what it is, the date, the amount, how often it happens and what I could do about it. Then add up what fees, interest and double charges cost me over the whole period.
The demo turned up these charges.
Charge | What the files showed | What to check next |
Card interest | $302.48 over six months, rising from $42.46 to $60.11 per month | Review the balance and interest on the card statement |
Bank fees | Six $12 service fees, a $35 overdraft fee, and a $9.37 foreign transaction fee | Ask the bank whether any fees can be waived |
Possible duplicate | BrightMart Online charged $86.40 twice on September 12 | Confirm both entries posted for the same purchase before disputing one |
Internet bill | Rose from $55 to $80 in August | Ask whether the old rate is still available |
Streamflix | Rose from $15.49 to $17.99 | Review the plan before downgrading or pausing |
Subscriptions | Five services at $141.95 a month, plus a $119.99 annual plan | Check which services you still use |
Fees, interest, and the duplicate add up to $505.25 in the demo. Including the extra amounts paid after the internet and Streamflix increases brings the total to $587.75.
If a charge has an explanation, such as a seasonal increase in your power bill, give Claude that context and ask it to update the table.
Step 5: Check the numbers
Pick a figure you plan to act on and ask for the underlying transactions. Replace “bank fees” with the item you want to verify.
Which transactions make up the bank fees total? List each one with its date, the merchant and the amount, then add them up with code.
In the demo, eight transactions add up to $116.37 in bank fees. The $302.48 in card interest appears separately.
Then ask Claude to review how it counted the rows.
Check your own work. Did you count any card payment or transfer between my accounts as spending or income, count a transaction twice, or include anything from outside the files? Fix the totals if so, and tell me what changed.
The demo review kept the totals and found two issues in the write-up. A grocery figure had been rounded, and annual projections needed clearer labels. Compare at least one total against the CSV or your bank app before acting.
Use cases
Use case #1: Plan around your paydays
Ask Claude to estimate how a purchase would affect your checking balance.
Can I afford a $600 trip in December? Map December on a calendar with my paydays, my fixed bills and my average flexible spending, and show the lowest my checking balance would get.
Claude may build an interactive calendar that lets you move the purchase date. In the demo, the projected low was $1,261.23 on December 11, before the December 15 payday. Check the starting balance, paydays, and upcoming bills before relying on the projection.
Use case #2: Build a cancel list
Get recurring charges and expected renewal dates into one table.
List every subscription and membership I pay for, what each one cost over the whole period, and the date each one should renew next. Sort them by monthly cost.
The six demo subscriptions cost $824.21 over the period. Their monthly equivalent is $151.95 after spreading the annual plan across 12 months. Check estimated renewal dates against the latest charge or the service’s billing page.
Use case #3: See what card interest cost you
Ask for the interest charges by month and which details the file can support.
What's an APR, and what has card interest cost me in these files? Show the interest month by month, explain why it changed, and tell me what you can't work out from these files.
A transaction CSV can show interest charges without listing the rate or explaining why the amount changed. Look up your actual APR in your card statement or app.
You can use the same approach for a pitch deck outline, a sponsor reply, or a weekly report. Choose tests that would catch a mistake you’d otherwise have to fix later.
Use case #4: Draft a duplicate-charge dispute
Once you’ve confirmed a duplicate, use the two transactions to draft a message.
Write a short message to my card company disputing a duplicate charge. Use the two matching transactions in my card file, with the merchant, date and amount, and ask for one of them to be refunded.
Before sending, check the merchant, date, amount, and name in the signature.
Limitations
The audit covers the accounts and dates in the files you upload. Pending charges, unexported accounts, and details such as your APR may be missing.
Review the fee list row by row. A merchant such as Bean There Coffee contains the letters fee, but the merchant name alone tells you nothing about the type of charge. Claude excluded it in the demo.
Statement uploads follow your usual Claude chat privacy settings. Remove identifying details before uploading, and check any draft for a signature Claude may have filled in from your account.
As checked for the original guide on November 12, 2026, Projects and code execution were available on Free, with up to five Projects. The stated chat upload limits were 500 MB per file and 20 files per chat. Claude’s separate Personal Finance feature uses Plaid for bank connections and was listed as US-only on Pro, Max, and Ultra. This walkthrough uses CSV exports.
Closing
Run Steps 3 to 5 with the demo files first and compare Claude’s totals with the kit’s answer sheet. Then repeat the audit with six months of your own transactions.
For your next monthly review, open a fresh chat in the same Project and attach the two months you want to compare.
See you in the next one :)