Wow. That's a lot of votes for all-cash as a way to cut spending. Are you all using currency or debit cards? If currency, how often do you have to hit the ATM?
Before last week, I had two debit cards in my wallet, my PenFed Visa, and cash. I rarely had cash and tried to use my PenFed card for everything (thinking along the lines of "I'm getting 1.25%/2%/5% cash back").
My new approach is to take the debit cards and the PenFed card out of my wallet and leave them in the coin box in my car. If I do spend money, this one step makes it slightly inconvenient for me...I have to deliberately grab one of the cards.
The second part of my approach is to use the debit cards for most purchases. For my mental framework, using the debit card hurts more than the Visa for two reasons: (1) I know the money is actually leaving my account in the next day or two instead of the end of next month when my credit card payment occurs, and (2) My bank accounts to which my debit cards are attached have a finite amount of money in them (usually a few hundred to a few thousand -- the rest I sweep into savings or investments); my credit card has, for all intents and purposes no upper limit (my credit limit is $50K, which is about 35 times the max balance I've ever had on that card). Both of these points inhibit the amount I spend.
For example, my team at work goes out for birthday lunches once a month. Before, when I used my credit card, I'd be more generous with what I ordered and with the tip. Now I am more reasonable on both items. I spend $10 instead of $13. That $3 doesn't seem like a lot, but it's a 30% difference in spending; if I do that with every purchase I've reduced that portion of my budget by 30%, which can add up to decent amounts of money.
It may be for me that spending actual cash would be more mentally painful than using my debit card and thus save me even more money. But in my case I don't consider the hassle of going to the bank and the risk of theft and loss to be worth it.
I actually still use my PenFed card for gas. It gives me 5% off, and I am fairly convinced that I don't buy more gas with my credit card than I would with a debit card; I just fill up whenever I need to.
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