I Tried the '30-Day Bookkeeping Method' for a Week: Here's Where My Money Went
I won’t be embarrassed to admit: I always thought I was pretty thrifty, but every month-end when I checked my bank balance, I’d ask myself—where did all my money go?
This went on for years. Until last week, when I decided to run an experiment: seriously track my spending for one week to see exactly where my money was flowing.
The results really shocked me.
First, what is this “30-Day Bookkeeping Method”?
I didn’t invent this method—it’s a popular personal finance introduction technique circulating online. The core is simple: for 30 consecutive days, record every single expense, no matter how small.
Not vague “spent 3000 this month,” but detailed “coffee 25, taxi 18, fruit 32…”
After recording, categorize and summarize to see what’s necessary and what can be cut.
I only stuck with it for one week (30 days is too hard!), but I already gained a lot.
My Week’s Spending: Several Surprising Discoveries
Starting with the total: 1,864 yuan in 7 days. Averaging 266 per day, that’s about 8,000 a month. At least 30% higher than I expected.
Looking at categories, here are my surprising findings:
First, food delivery and coffee cost more than I thought.
I tracked: ordered delivery 5 times in a week, spending 287 yuan. One coffee daily (sometimes two), 196 yuan in 7 days. These two items alone totaled 483 yuan—26% of total spending.
Honestly, I never thought this was a big expense before. Each delivery was just 20-30 yuan, coffee around 15—it felt like small change. But accumulated, it accounts for over a quarter.
Second, “while I’m at it” purchases are invisible killers.
Several times at convenience stores and supermarkets checking out, I’d grab snacks, drinks, or small items. Each purchase wasn’t expensive—5, 10, 15 yuan.
But over the week, these “impulse purchases” totaled 127 yuan. Average under 15 yuan each, but the frequency was too high.
The most extreme case: I went to a convenience store for a bottle of water (3 yuan), but grabbed chips, ice cream, and tissues on the way out. Final bill: 47 yuan.
Third, transportation costs have huge flexibility.
My weekly transportation was 213 yuan total. Of that, taxis 156, public transit 57.
The issue: most of those taxi rides could have been subway or bus. Just because “didn’t want to wait,” “in a hurry,” or “it’s raining,” I chose the more expensive option.
If I’d used all public transit, transportation costs could have been cut by at least half.
The Biggest Change Bookkeeping Brought Me
After a week of tracking, my biggest gain wasn’t knowing how much I spent, but gaining “awareness” of my spending habits.
Before, when spending money, I didn’t think. Wanted coffee? Bought it. Hungry? Ordered delivery. Going out? Called a taxi. Money flowed away bit by bit, but I felt nothing.
After bookkeeping, before every purchase, I’d subconsciously think: this needs to be recorded. This simple action gave me an extra second of thinking time.
Just that extra second helped me avoid several impulse purchases. Like once when scrolling through live-stream shopping, I almost bought a “looks useful” small appliance, but the thought of recording it made me hesitate. Later I realized, I didn’t really need it.
My Money-Saving Action Plan
Based on this week’s discoveries, I set several small goals:
Reduce delivery frequency from 5 times a week to 2. Cook at home or eat at the cafeteria other times. Estimated monthly savings: 400-500 yuan.
Switch to homemade pour-over coffee. Buying a dripper and beans drops cost per cup from 15 to 3 yuan. Saving 12 daily, 360 monthly.
Establish a “cooling-off period.” For any non-essential, add to cart first, decide 48 hours later whether to buy. This cuts most impulse purchases.
Fixed monthly savings. On payday, transfer savings to another card first—whatever remains is for spending.
About Bookkeeping Tools
This week I used the most primitive method: phone notes. Recorded every purchase, then organized into Excel each evening.
Though tedious, it worked well. Because the manual recording process itself is a reflection process.
If you find it too troublesome, budgeting apps work too. Many options available, features are similar. The key is “tracking,” not “what tool you use.”
Final Thoughts
Bookkeeping sounds simple but requires some discipline. I almost missed recording several times this week—luckily caught and filled in later.
But if you can stick with it for a month, you’ll have a completely new understanding of your financial situation. Not vague “probably spent quite a bit,” but clear “this money went here, was it worth it.”
This “awareness” itself is the best financial education.
Do you have a bookkeeping habit? If yes, what are your tips? If not, would you try it? Let’s chat in the comments.