How to calculate interest payments without EBIT
The actual financial statements should always be referenced first before opening or closing a position. For US companies, they are freely available on EDGAR.  Annual reports are called 10-Ks, and quarterly reports are called 10-Qs. YHOO and GOOG do a great job of posting financials that are quickly available, but money.msn has the best.  These should be starting point, quick references.  As you can see, they may all have the same strange accounting. Sometimes, it's difficult to find the information one seeks in the consolidated financial statements as in this case, so searching through the filing is necessary. The notes can be helpful, but Ctrl-F seems to do everything I need when I want something in a report. In AAPL's case, the Interest expense can be found in Note 3.
no interest expense (no debt in the capital structure) and an income tax benefit is one possible scenario. you determine this through the financial statement by looking for the differences between the E and EBIT in those calculations (interest and taxes).   of course, extraordinary items and discontinued operations could also be present, and result in the difference noted. As mentioned in other answers the interest you make is negligible and the calculations would depend on the bank. In saying that the general trend is calculate daily, pay monthly.  A typical scenario would be that every night at midnight the interest for your account at that point in time is calculated. This occurs every midnight and at the end of the month the sum of those calculations will be added to your account. You could have had several significant transactions pass through your account in one day although if the interest is calculated at a specific point in time some transactions may not contribute to any interest. These calculations are worth thinking about,  even in circumstances of negligible returns, as it could assist when considering combining credit cards with home loan offset accounts so it is not a complete waste of time to understand how interest is calculated. The more you know ;) "I recently needed to compute a better balance that let us pick and choose what to include in the computed sum without losing information, so I revisited this topic and I'm pleased to say that I've found a solution that works (at least for our data - you may have transactions that this code doesn't recognize, but you can always modify it to match). My solution was written natively for MS SQL Server 2008 or later, it uses a scalar UDF, a VIEW, and a windowed aggregate (SUM OVER (ORDER BY ...) which means it should be almost-syntax compatible with PostgreSQL. MySQL does not support OVER but you can perform a running-sum using a variable with arithmetic addition directly in the SELECT clause. Create a database table with this schema (feel free to exclude columns you're not interested in, such as Option1Name): Create a UNIQUE index on TxnId - you could use it as a primary-key, I suppose. You might be tempted to create a Foreign-Key relationship between ReferenceTxnId and TxnId, however this will fail if you enforce it: we have many transactions where ReferenceTxnId points to a Transaction that doesn't exist. This is usually in the case of [Type] = 'Web Accept Payment Received' AND [Status] = 'Canceled'. We also have some TransactionId values longer than 17 characters: some TransactionIds start with ""U-"" - all pending money requests, I suspect this indicates the transaction is ""unfinished"". Re-download your entire PayPal History CSV files so that you have the latest retroactive updates. Import these CSV files into this PayPalHistory table. Do a simple test to see how bad PayPal's default data is: To find out where the differences are coming from, run this query: (The ORDER BY (...), RowId is to ensure consistent ordering when multiple transactions share the same timestamp) As you scroll through the results, you'll see how the naive SUM is thrown-off from the official PayPal-computed Balance column. So as you can see, the Net column value cannot always be trusted - what we need is to generate our own ""EffectiveNet"" value which is accurate - that is, the value is 0.00 for rows which do not affect the balance, instead of being what they are right now. The problem is, given a single row of data (such as any single row from the example table in my original Question) we have no way of inherently knowing what its ""EffectiveNet"" is. I have devised two functions to help solve this problem, the first function only looks at the ReferenceTxnId, Type and Status column values and generates accurate values for the vast majority of rows - indeed, in our dataset we only had one row for which this approach did not work. I recommend you try this one first and compare the running-sum value to ensure it works for your data: You can use this function in the query like so below, hopefully it should give you an accurate running-sum and balance figure at the end: 8. And here's the view that ties it all together: Used like so: I hope this helps anyone else wanting to do accurate bookkeeping with PayPal Transaction History files!" There is a way to get a reasonable estimate of what you still owe, and then the way to get the exact value. When the loan started they should have given you amortization table that laid out each payment including the principal, interest and balance for each payment. If there are any other fees included in the payment those also should have been detailed. Determine how may payments you have maid: did you make the first payment on day one, or the start of the next month? Was the last payment the 24th, or the next one? The table will then tell you what you owe after your most recent payment. To get the exact value call the lender. The amount grows  between payment due to the interest that is accumulating. They will need to know when the payment will arrive so they can give you the correct value. To calculate how much you will save do the following calculation: payment = monthly payment for principal and interest paymentsmade =Number of payments made = 24 paymentsremaining = Number of payments remaining = 60 - paymentsmade = 60-24 = 36 instantpayoff = number from loan company  savings = (payment * paymentsremaining ) - instantpayoff "Its called a ""Grace Period"" and you are not paying interest on the 0% BT, you are paying interest on the amount you spent in purchases If you do not pay your balance in full by the due date your grace period ends. This means that you have to pay interest on the purchased amount from the day it is made. This is why when you do a balance transfer the card should be put in the Sock Drawer until the BT is paid off. In order to restore the grace period you must pay the balance in full and the grace period will start during the Next Payment Cycle. Lets Assume: Statement cuts on the 1st and Due date is the 20th. you make the minimum payment of $10 Balance now is $100 Since you have a balance of $100 from the previous statement and a new purchase of $50.00, when the next statement cuts you will have to pay interest according to the terms on the $50.00 portion. In order to get the grace period back you will have to pay in full and wait for the next cycle In case I did not explain it well here is a quote from creditcards dot com website: The cost of carrying a balance   This is because carrying a balance of   any size into the next billing cycle means there is no grace period on   your purchases during that cycle. The card company will begin charging   interest on your purchases the day you make them. So leaving even $1   in unpaid balance on your card will cost you considerably more than   the measly finance charges on that dollar. To see how this works let's consider an imaginary card user named   Sally. She's so happy she got a new credit card that she charges   $1,500 in purchases on the first day of her monthly billing cycle.   After the cycle ends, Sally pays off the entire $1,500 by the due   date, wiping her balance to zero. As a result, her purchases during   the second month are also free of interest. She has used her grace   period wisely to avoid finance charges. What happens if Sally leaves just $1 of her balance from the first   month unpaid? That $1 begins to accrue interest starting the first day   of the billing cycle. It's just $1, so the interest is not a big deal   -- but because she used up her grace period without paying off her entire debt, her new purchases during the second month also start to   get hit with interest charges immediately, starting the day of the   transaction. Assuming she makes another $1,500 in purchases at the   average annual interest rate of about 13 percent, that means $16 in   finance charges for the month. If Sally repeats this pattern, the   interest costs add up to $190 over the course of a year." It is pretty easy to setup a spreadsheet for calculating interest payments and remaining balance.  Do a quick search online.  You may want to put it in something like Google Docs, where brother can view the status, but only you can edit it.  When you get a payment, a portion goes to interest and another to principle.  The formulas will do the work for you. However, I feel that there is a bigger issue.  The math may seem like a good deal for the both of you, but I would be very hesitant to loan a family member money. What if he does not pay?  What if he is late with a payment and goes on a vacation himself?  What if his significant other resents the payment that you collect which precludes her from  buying a new TV, etc... People come to hate/resent big corporations that they have to make payments.  How much more so one that has a face....that comes over and eats?  While this loan is outstanding holidays may never be the same.   Is the loan a real need?  Are you in a position to give them the money?  You may want to consider the latter. Is there a reason he can't just borrow the money from the bank? Interest per month is 12th root of annual interest, or a multiplier of about 1.0327%. At end of 1st month, you start with $0, add interest on $0, and add $600, getting $600. 2nd month: start with $600, add 0.0327% interest plus $600, getting $1219.62. 3rd: balance plus interest plus deposit yields $1859.50 Repeat ad nauseam. Easier with a spreadsheet or a bit of trivial programming. Or you can try to re-derive the formulas, but that is left as an exercise for the student. I have found a good explanation here: http://www.contracts-for-difference.com/Financing-charge.html Financing is calculated by taking the overall position size, and multiplying it by (LIBOR + say 2%) and then dividing by 365 x the amount of days the position is open. For instance, the interest rate applicable for overnight long positions may be 6% or 0.06. To calculate how much it would cost you to hold a long position for X number of days you would need to make this 'pro rata' meaning that you would need to divide the 0.06 by 365 and multiply it by X days and then multiply this by the trade size. So for example, for a trade size of $20,000, held for 30 days, the interest cost would be about $98.6. It is important to note that due to financing, long positions held for extended periods can reduce returns. Unless you are getting the loan from a loan shark, it is the most common case that each payment is applied to the interest accrued to date and the rest is applied towards reducing the principal.  So, assuming that fortnightly means 26 equally-spaced payments during the year, the interest accrued at the end of the first fortnight is $660,000 x (0.0575/26) = $1459.62 and so the principal is reduced by $2299.61 - $1459.62 = $839.99 For the next payment, the principal still owing at the beginning of that fortnight will be $660,000-$839.99 = $659,160.01 and the interest accrued will be $659,160.01 x (0.0575/26) = $1457.76 and so slightly more of the principal will be reduced than the $839.99 of the previous payment.  Lather, rinse, repeat until the loan is paid off which should occur at the end of 17.5 years (or after 455 biweekly payments). If the loan rate changes during this time (since you say that this is a variable-rate loan), the numbers quoted above will change too. And no, it is not the case that just %5.75 of the $2300 is interest, and the rest comes off the principle (sic)? Interest is computed on the principal amount still owed ($660,000 for starters and then decreasing fortnightly). not the loan payment amount. Edit  After playing around with a spreadsheet a bit, I found that if  payments are made every two weeks (14 days apart) rather than 26 equally spaced payments in one year as I used above, interest accrues at the rate of 5.75 x (14/365)% for the 14 days rather than at the rate of (5.75/26)% for the time between payments as I used above each 14 days, $2299.56 is paid as the biweekly mortgage payment instead of the $2299.61 stated by the OP, then 455 payments (slightly less than 17.5 calendar years when leap years are taken into account) will pay off the loan.  In fact, that 455-th payment should be reduced by 65 cents.  In view of rounding of fractional cents and the like, I doubt that it would be possible to have the last equal payment reduce the balance to exactly 0. There is no interest outstanding, per se.  There is only principal outstanding.  Initially, principal outstanding is simply your initial loan amount. The first two sections discuss the math needed - just some arithmetic. The interest that you owe is typically calculated on a monthly basis.  The interested owed formula is simply (p*I)/12, where p is the principal outstanding, I is your annual interest, and you're dividing by 12 to turn annual to monthly. With a monthly payment, take out interest owed.  What you have left gets applied into lowering your principal outstanding.  If your actual monthly payment is less than the interest owed, then you have negative amortization where your principal outstanding goes up instead of down. Regardless of how the monthly payment comes about (eg prepay, underpay, no payment), you just apply these two calculations above and you're set.  The sections below will discuss these cases in differing payments in detail. For a standard 30 year fixed rate loan, the monthly payment is calculated to pay-off the entire loan in 30 years.  If you pay exactly this amount every month, your loan will be paid off, including the principal, in 30 years.  The breakdown of the initial payment will be almost all interest, as you have noticed.  Of course, there is a little bit of principal in that payment or your principal outstanding would not decrease and you would never pay off the loan. If you pay any amount less than the monthly payment, you extend the duration of your loan to longer than 30 years.  How much less than the monthly payment will determine how much longer you extend your loan.  If it's a little less, you may extend your loan to 40 years.  It's possible to extend the loan to any duration you like by paying less.  Mathematically, this makes sense, but legally, the loan department will say you're in breach of your contract. Let's pay a little less and see what happens.  If you pay exactly the interest owed = (p*I)/12, you would have an infinite duration loan where your principal outstanding would always be the same as your initial principal or the initial amount of your loan.   If you pay less than the interest owed, you will actually owe more every month.  In other words, your principal outstanding will increase every month!!!  This is called negative amortization.  Of course, this includes the case where you make zero payment.  You will owe more money every month. Of course, for most loans, you cannot pay less than the required monthly payments.  If you do, you are in default of the loan terms. If you pay more than the required monthly payment, you shorten the duration of your loan.  Your principal outstanding will be less by the amount that you overpaid the required monthly payment by.  For example, if your required monthly payment is $200 and you paid $300, $100 will go into reducing your principal outstanding (in addition to the bit in the $200 used to pay down your principal outstanding).  Of course, if you hit the lottery and overpay by the entire principal outstanding amount, then you will have paid off the entire loan in one shot! When you get to non-standard contracts, a loan can be structured to have any kind of required monthly payments.  They don't have to be fixed.   For example, there are Balloon Loans where you have small monthly payments in the beginning and large monthly payments in the last year.   Is the math any different?  Not really - you still apply the one important formula, interest owed = (p*I)/12, on a monthly basis.  Then you break down the amount you paid for the month into the interest owed you just calculated and principal.  You apply that principal amount to lowering your principal outstanding for the next month. Supposing that what you have posted is accurate, the most likely scenario is that you have a structured 5 year car loan where your monthly payments are smaller than the required fixed monthly payment for a 5 year loan, so even after 2 years, you owe as much or more than you did in the beginning!  That means you have some large balloon payments towards the end of your loan.  All of this is just part of the contract and has nothing to do with your prepay. Maybe I'm incorrect in my thinking, but I have a question about   prepaying a loan. When you take out a mortgage on a home or a car   loan, it is my understanding that for the first years of payment you   are paying mostly interest. Correct. So, let's take a mortgage loan that allows prepayment without penalty.   If I have a 30 year mortgage and I have paid it for 15 years, by the   16th year almost all the interest on the 30 year loan has been paid to   the bank and I'm only paying primarily principle for the remainder of   the loan. Incorrect.  It seems counter-intuitive, but even in year 16, about 53% of your monthly payment still goes to interest!!!  It is hard to see this unless you try to do the calculations yourself in a spreadsheet. If suddenly I come into a large sum of money and decide I want to pay   off the mortgage in the 16th year, but the bank has already received   all the interest computed for 30 years, shouldn't the bank recompute   the interest for 16 years and then recalculate what's actually owed in   effect on a 16 year loan not a 30 year loan? It is my understanding   that the bank doesn't do this. What they do is just tell you the   balance owed under the 30 year agreement and that's your payoff   amount. Your last sentence is correct.  The payoff amount is simply the principal outstanding plus any interest from (p*I)/12 that you owe.  In your example of trying to payoff the rest of your 30 year loan in year 16, you will owe around 68% of your original loan amount. That seems unfair. Shouldn't the loan be recalculated as a 16 year   loan, which it actually has become? In fact, you do have the equivalent of a 15 year loan (30-15=15) at about 68% of your initial loan amount.  If you refinanced, that's exactly what you would see.  In other words, for a 30y loan at 5% for $10,000, you have monthly payments of $53.68, which is exactly the same as a 15y loan at 5% for $6,788.39 (your principal outstanding after 15 years of payments), which would also have monthly payments of $53.68. A few years ago I had a 5 year car   loan. I wanted to prepay it after 2 years and I asked this question to   the lender. I expected a reduction in the interest attached to the car   loan since it didn't go the full 5 years. They basically told me I was   crazy and the balance owed was the full amount of the 5 year car loan.   I didn't prepay it because of this. That is the wrong reason for not prepaying.  I suspect you have misunderstood the terms of the loan - look at the Variable Monthly Payments section above for a discussion.   The best thing to do with all loans is to read the terms carefully and do the calculations yourself in a spreadsheet.  If you are able to get the cashflows spelled out in the contract, then you have understood the loan. Question is, what is this number 0.01140924 13.69/12=0.01140924 In addition, how does one come out with the EIR as 13.69% pa? When calculating payments, PV = 9800, N=36 (months), PMT=333.47, results in a rate of 1.140924% per period, and rate of 13.69%/yr. No idea how they claim 7.5% In Excel, type =RATE(36,333.47,-9800,0,0) And you will get 1.141% as the result.  36 = #payments, 333.47 = payment per period, -9800 is the principal (negative, remember this) And the zeros are to say the payments are month end, second zero is the guess.  Edit - I saw the loan is from a Singapore bank. It appears they have different rules on the rates they quote. As quid's answer showed the math, here's the bank's offer page -  The EIR is the rate that we, not just US, but most board members, are used to. I thought I'd offer an example using a 30 year mortgage.   Yo can see above, a 6% fixed rate somehow morphs into a 3.86% AR. No offense to the Singapore bankers, but I see little value in this number. What surprises me most, is that I've not seen this before.  What's baffling is when I change a 15yr term the AP drops to less than half. It's still a 6% loan and there's nothing about it that's 2 percent-ish, in my opinion.  Now we know. It depends on your bank and the details in the agreement, but typically, interest is calculated daily. So if you borrow 1000 EUR for 1 day, you pay 15% * 1000 EUR * 1/360 = 42 Cent (41.666667 cent to be exact). You can simply multiply these 42 cent up with the number of days you plan and the number of 1000s EUR. Note that weekend days count too, even if you cannot pay them back on the weekend. The exact value will be very slightly different, as the interest is added monthly to the principal, and there is compound interest on the interest. Banks also often consider all months 30 days long for interest calculations. If you're not worried about making the car loan payments, why would you want to pay off a loan that is not charging you any interest? Pay off the interest bearing student loan. There's not quite enough to answer the question in full. For the two years of non-payment, were there any penalties, or just accrued interest? If no penalties, this is a 3 step time-value-of-money calculation. First, take the terms of the loan and figure out the balance after 5 years.  Second, for two years, increase the balance by the monthly interest rate.  Last, calculate a new payment with a 13 year duration.  Excel or any business calculator can handle this. "To calculate the balance (not just principal) remaining, type into your favorite spreadsheet program: It is important that the periods for ""Periods"" and ""Rate"" match up.  If you use your annual rate with quarterly periods, you will get a horribly wrong answer. So, if you invest $1000 today, expect 6% interest per year (0.5% interest per month), withdraw $10 at the end of each month, and want to know what your investment balance will be 2 years (24 months) from now, you would type: And you would get a result of $872.84. Or, to compute it manually, use the formula found here by poster uart:   This is often taught in high-school here as a application of geomentric series. The derivation goes like this.  Using the notation :  r = 1 + interest_rate_per_term_as_decimal p = present value a = payment per term eot1 denotes the FV at end of term 1 etc.  eot1: rp + a   eot2: r(rp + a) + a = r^2p + ra + a   eot3: r(r^2p + ra + a) + a = r^3p + r^2a + ra + a ...   eotn: r^np + (r^(n-1) + r^(n-2) + ... 1)a = p r^n + a (r^n - 1)/(r-1)  That is, FV = p r^n + a (r^n - 1)/(r-1).   This is precisely what exel [sic] computes for the case of payments made at the end of each term (payment type = 0). It's easy enough to repeat the calculations as above for the case of payments made at the beginning of each term. This won't work for changing interest rates or changing withdrawal amounts.  For something like that, it would be better for you (if you don't want online calculators) to set up a table in a spreadsheet so you can adjust different periods manually."