Tax Write-offs and knowing how much I need to spend before the end of the year
"(I'm assuming USA tax code as this is untagged) As the comments above suggest there is no ""right"" answer or easy formula.  The main issue is that you likely got into business to make money and if you make money consistently you will pay taxes.  Reinvesting generally should be a business decision where the main concern is revenue growth and taxes are an important but secondary concern. Taxes can be complicated, but for a small LLC shouldn't be that bad.  I highly recommend that you take some time closely analyze your business and personal taxes for the previous year.  Once you understand the problem better, you can optimize around it.  If it is a big concern, some companies buy software so they can estimate their taxes periodically through the year and make better decisions."
Gosh don't do either!  Unless you are fully funding you ROTH accounts and even then I wouldn't do it.  Those interest rates are free money.   You are giving away the best bargain in the history of home mortgages. Don't you think you can make more than 4% on your money invested?   Don't you think in 5 years you will be able to make 4% on bond/cd's/ and other low risk investments? Don't forget money you pay in the 2020's on beyond to your mortgage are inflationary dollars.  Do you think that money will be more valuable in the 20's and beyond? I don't.  Roths are free money too.  Think if you put 11k in there a year how much would you have at the end of it tax free.  There is a reason you can only put $5,500 in them, they are too good a deal tax wise to let people put too much in there. Think about this my parents bought their home in 1967 their mortgage was $170 a month.  Inflation hits and the interest they are paying at 8%! mind you, it was still a laughable amount of money each month for mortgage payment from 1977 and on. Also I bought a $450,000 house 38 months ago.  Instead of putting down 180 I put down 80 I let the other 100k in my investment account and moved 5.5k over to Roth every year. I now have a roth worth $38k and an investment account worth $105k.  I made 40k on my money those three years and the 38k is tax free! If you don't believe me call the help line at clarkhoward.com  Get over the emotional need to be debt free and make a logical finical choice.  I am begging you to think about this.  This post could save you tens of thousands of dollars. Let me put it one more way.  100k in debt with 100k in investments is debt free living.  Especially when you debt is under 4% and a tax write off. Paying the minimum balance on a loan can be DEVASTATING and is highly UN-RECOMMENDED. It is important you understand your loan and the terms associated with it. Loans are given for a period of time but if you pay the minimum it does NOT mean you will pay it all off by the end. When paying a loan money is applied to the interest first and any extra amount is then applied to the principle. Here's an example: If I have a $12 loan for 1 year. The interest is 100%. My minimum payment each month is $1. If I pay that minimum only I will be stuck paying $12 at the end of the loan. Why you ask? because each month I'm being charged $1 interest and the payment I am making is only going towards that interest. However if I paid $2 instead now $1 goes to the principal (the original $12 I borrowed). This means that next month I will only be charged interest on $11 dollars instead of $12. You need to know how much is going towards the interest of your loan and how much is going towards the principle you can speak with your bank about this and they will help you understand. In many cases they actually provide you with the numbers on your statment with examples of how long it would take to payoff your loan with minimum only and how long it would take if you added an extra x amount each month. I recommend using the Snowball Method to pay of your debt. It's simple and effective. How much you should add to each monthly payment depends on how much you can afford to add. Here are some calculators you can play around with: CNN Money Bank Rate Calc Edit: So with the additional information you provided we can estimate that you have about 2200 free cash flow each month(that's your cash after you pay all your bills). We can put away 500 each month for a rainy day fund, just to be safe.(job loss, accidents, or anything we can't predict) So assuming that is all your expenses including the money you spend on entertainment. That leaves you with $1700 you can add on to your loan payments. So you can pay off your third loan in 1 month. Then add the remaining balance to the 2nd loan. With this income it should take you less then a year to pay off all your loans. If your employer is matching 50 cents on the dollar then your 401(k) is a better place to put your money than paying off credit cards This.  Assuming you can also get the credit cards paid off reasonably soon too (say, by next year).  Otherwise, you have to look at how long before you can withdraw that money, to see if the compounded credit card debt isn't growing faster than your retirement.  But a guaranteed 50% gain, your first year is a pretty hard deal to beat. And if you currently have no savings, unless all of your surplus income has been reducing your debt, you're living beyond your means. You should be earning more than you're (going to be) spending, when you start paying rent/car bills.  If you don't know what this is going to be, you need to be budgeting.   Get this under control, by any means necessary.  New job/career?  Change priorities/expectations?  Cut expenses?  Live to your budget?  Whatever it takes. I don't think you should be in any investment that includes bonds until you're 40, and maybe not even then - equities and cash-equivalents all the way (cash is for emergency funds, and for waiting for buying opportunities).  Otherwise Michael has some good ideas. I would caveat that I think you should not buy any investments in one chunk, but dollar average it over some period of time, in case the market is unnaturally high right when you decide to invest. You should also gauge possible returns and potential tax liabilities. Debt is good to get rid of, unless it is good debt (very low interest rates - ie: lower than you could borrow the money for).  Good debt should still get paid off - who knows how long your job could last for - but maybe not dump all of your $50K on it. Roth is amazing.  You should be maxing that contribution out every year. Basically you have 4 options: Use your cash to pay off the student loans. Put your cash in an interest-bearing savings account. Invest your cash, for example in the stock market. Spend your cash on fun stuff you want right now. The more you can avoid #4 the better it will be for you in the long term. But you're apparently wise enough that that wasn't included as an option in your question. To decide between 1, 2, and 3, the key questions are:  What interest are you paying on the loan versus what return could you get on savings or investment?  How much risk are you willing to take? How much cash do you need to keep on hand for unexpected expenses? What are the tax implications? Basically, if you are paying 2% interest on a loan, and you can get 3% interest on a savings account, then it makes sense to put the cash in a savings account rather than pay off the loan. You'll make more on the interest from the savings account than you'll pay on interest on the loan. If the best return you can get on a savings account is less than 2%, then you are better off to pay off the loan. However, you probably want to keep some cash reserve in case your car breaks down or you have a sudden large medical bill, etc. How much cash you keep depends on your lifestyle and how much risk you are comfortable with. I don't know what country you live in. At least here in the U.S., a savings account is extremely safe: even the bank goes bankrupt your money should be insured. You can probably get a much better return on your money by investing in the stock market, but then your returns are not guaranteed. You may even lose money. Personally I don't have a savings account. I put all my savings into fairly safe stocks, because savings accounts around here tend to pay about 1%, which is hardly worth even bothering. You also should consider tax implications. If you're a new grad maybe your income is low enough that your tax rates are low and this is a minor factor. But if you are in, say, a 25% marginal tax bracket, then the effective interest rate on the student loan would be more like 1.5%. That is, if you pay $20 in interest, the government will then take 25% of that off your taxes, so it's the equivalent of paying $15 in interest. Similarly a place to put your money that gives non-taxable interest -- like municipal bonds -- gives a better real rate of return than something with the same nominal rate but where the interest is taxable. My wife and I meet in the first few days of each month to create a budget for the coming month. During that meeting we reconcile any spending for the previous month and make sure the amount money in our accounts matches the amount of money in our budget record to the penny. (We use an excel spreadsheet, how you track it matters less than the need to track it and see how much you spent in each category during the previous month.)  After we have have reviewed the previous month's spending, we allocate money we made during that previous month to each of the categories. What categories you track and how granular you are is less important than regularly seeing how much you spend so that you can evaluate whether your spending is really matching your priorities. We keep a running total for each category so if we go over on groceries one month, then the following month we have to add more to bring the category back to black as well as enough for our anticipated needs in the coming month. If there is one category that we are consistently underestimating (or overestimating) we talk about why. If there are large purchases that we are planning in the coming month, or even in a few months, we talk about them, why we want them, and we talk about how much we're planning to spend. If we want a new TV or to go on a trip, we may start adding money to the category with no plans to spend in the coming month. The biggest benefit to this process has been that we don't make a lot of impulse purchases, or if we do, they are for small dollar amounts. The simple need to explain what I want and why means I have to put the thought into it myself, and I talk myself out of a lot of purchases during that train of thought. The time spent regularly evaluating what we get for our money has cut waste that wasn't really bringing much happiness. We still buy what we want, but we agree that we want it first. "Gail Vaz-Oxlade from the television show Til Debt Do Us Part has a great interactive budget worksheet that helps you set up a ""jar"" or envelope system for each month based on your income and fixed expenses.  We have used this successfully in the past.  What we found most useful was, as others have said, writing everything down, keeping receipts, and thus being accountable and aware of our spending." Don't overthink it. As an employee, whether of your own corporation or of someone else, you get a salary and there are deductions taken out. As the owner of a business you get (hopefully) business profits as well. And, in general, you often have other sources of income from investments, etc. Your estimated tax payments are based on the difference between what was withheld from your salary and what you will owe, based on salary, business income, and other sources. So, in essence, you just add up all the income you expect, estimate what the tax bill will be, and subtract what's been withheld. That's your estimated tax payment. I use a spreadsheet for that.   I provide house value, land value, closing/fix-up costs, mortgage rate and years, tax bracket, city tax rate, insurance cost, and rental income.  Sections of the spreadsheet compute (in obvious ways) the values used for the following tables:  First I look at monthly cash flow (earnings/costs) and here are the columns:   Next section looks at changes in taxable reported income caused by the house,  And this too is monthly, even though it'll be x12 when you write your 1040.   The third table is shows the monthly cash flow, forgetting about maintenance and assuming you adjust your quarterlies or paycheck exemptions to come out even: Maintenance is so much of a wildcard that I don't attempt to include it.  My last table looks at paper (non-cash) equity gains:  I was asked how I compute some of those intermediate values.  My user inputs (adjusted for each property) are:  My intermediate values are: