I did a year-end inventory on my finances and 4 mistakes cost me the most money

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• Every December, I do an annual review of my finances.
• This year, I noticed that holiday overspending pushed me off track.
• I also lost money by ignoring my investment mistakes, keeping too much money in cash, and paying for subscriptions I didn't use. 

After spending most of my 20s making too many ongoing financial mistakes, from racking up credit card debt to overlooking a retirement fund, I've made a promise to myself that my 30s would be different. That's why, for the past few years, I've spent quality time managing my finances and trying to limit money mistakes.

One way I do that is by spending time in December doing a year-end inventory on all of my finances. I look at how much I spent every month, how each of my investments did, and the amount of cash I was able to save over the course of the year.

After finishing my financial inventory for this year, I noticed four big money-costing mistakes. Here's what I did wrong in 2022 that I vow not to repeat again in 2023. 

1. Overspending during the holiday season

One of the biggest ongoing mistakes I make every year is overspending during the holiday season.

For most of the year, I stick to a strict spending budget and monitor where every dollar is going on a weekly basis. However, when the month of November happens, my financial mindset seems to change. Rather than sitting down and planning out a budget for holiday gifts, I give into promotions from retailers and the influence of big deal-days, like Black Friday and Cyber Monday, to buy as many items as I can for those on my gift list.

In the past month and a half, I spent more than $750 more than my monthly budget allowed for not only gifts, but holiday outings, and even travel. 

To prevent this from happening next year, I want to make a gift list budget during the first two weeks of November and monitor my spending on a daily basis, so I don't spend more than I planned. 

2. Keeping too much money in cash

With the threat of a looming recession in 2023, I've spent most of this year scared to make any big money moves with my cash. As a freelancer, I wanted to make sure that I had enough cash in my emergency fund and savings account to be able to cover expenses in case I lost any of my clients because of an economic downturn. 

Because of that, I missed out on opportunities to grow that money, in a low-risk way. When a lot of my friends were investing in I-Bonds earlier this year, when the interest rate was around 9%, I was too fearful that I needed that money, so I kept it in a savings account making 2% APY interest. 

I was slow to put the money in CDs earning 4% APY and because of that, I potentially lost out on a few thousand dollars that I could have made putting the money in a 12-month CD.

3. Not paying attention to my investments

At the start of this year, I decided to invest a few thousands dollars into a handful of individual stocks. I didn't do very much research into any of these companies and after I bought the stocks, I didn't pay attention to these investments for seven months.

During that time, most of the stock prices dropped significantly and I lost a lot of money. While these stocks might bounce back, it was reckless of me to invest in companies without doing research, seeking advice from a financial advisor, and not checking up on the market during the year.

In 2023, I plan to invest in index funds, which can help me diversify my portfolio and minimize the risk that can come from investing in individual companies. 

4. Forgetting to cancel subscriptions

While I kept up with routinely checking the spending on my personal credit cards every single week, I wasn't so good about monitoring recurring charges on my business credit cards.

When I looked back at my monthly statements, I noticed at least three recurring subscription charges for software and marketing tools that I didn't use more than a few times this year. If I would have noticed these charges six months ago, I would have canceled these subscriptions and saved a few hundred dollars.

To make sure this doesn't happen next year, I've made a list of all the subscriptions I have for my business currently (based on this year's credit card statements) and am starting to cancel all of the ones that aren't extremely necessary. That way, I can start the year with limited subscriptions and not worry about getting charged for products or software access that I don't routinely need.