Money Saved on finance charges
Avoiding a cost (interest) isn't quite the same as income. There is no entry, nothing for you to consider for this avoided interest.  What you do have is an expense that's no longer there, and you can decide to use that money elsewhere each month.
Probably not. A debit of 50K in your Bank statement does not mean that its invested into tax saving instrument. This question is best answered by the finance department of your company. Practise vary from organization to organization. To get a good estimate, go here  or other similar sites and see.  But basically, yes, you can save yourself a whole lot of money just by paying extra every month.  One note though, do make sure you are specifying that you want the money to go towards principal, not escrow or toward prepaying interest. The answer to question 1 is yes, you can always reduce your loan when you remortgage by introducing additional funds. There is some possibility a (relatively) small charge might be applicable for managing the marginally more complex transfer, but it shouldn't be too much.. The answer to question 2 is NONE of your over payment amounts would have gone on interest, but you MIGHT incur penalty charges. Interest is only charged on the outstanding loan amount (i.e. £100K initially, reducing to £85K over 2 years in your example) at the interest rate determined by your mortgage agreement - there is no 'paying off interest' as such. Over payments are essentially all capital payments, reducing the principal/loan amount, so no additional interest would be paid if you opted for over payments. If you used your £10K to made the over payments throughout the 2 year fixed period you would in fact have paid LESS interest by the end of the 2 years, because you would be reducing the loan amount at a quicker rate, and thus the interest you pay each month (based on the lower outstanding loan at that time) would be lower. BUT... over payments might have attracted over payment penalties (typically a percentage of the amount you pay) and these penalties often mean it's not worth doing. Most fixed term mortgages have such penalties, but it depends on the agreement, and many mortgages also allow you to make over payments up to a certain amount each year before you get hit. Edit (additional suggestion): If the example you provide is one based on what you expect might happen to you over the next couple of years, something you could CONSIDER is an offset mortgage. Here your £10K that you accumulate reduces your interest through the 2 years, but you keep it in savings where you can access it if you need to. Accessing it will then cause a corresponding rise in interest payments, but to no higher level than you would have been paying if you had nothing in the savings in the first place. You usually pay a slightly higher interest rate for these sort of mortgage, so it's impossible to know if it would be more economical, and how appropriate it would be for you in other respects depends on many factors. It really depends on the terms of your loan. For example, some loans have a pre-payment penalty. You will just have to ask your lender to know for sure. That said. In almost all cases, you can save considerable interest by making extra payments towards the principal. Be careful though, some lenders require you to specifically mark the payment to be applied to the loan principal and if you don't designate it as such, they will just apply it as an early payment for future months and not reduce your balance until that future payment is due, which doesn't help at all. Another option to reduce your total interest costs, though more common for larger loans like mortgages, is to split the payment into multiple parts and pay more than once a month instead of a single payment each month. This only works if they calculate interest daily and would be useless if they do it monthly. They key is knowing the terms of your loan. Despite it not being in their best interest (pun intended), most lenders will work with you on a strategy to help you minimize the interest cost in the name of customer service. "You're looking at the ""wrong"" credit. Here's the Wikipedia article about the bookkeeping (vs the Finance, that you've quoted) term." For the purpose of personal finance, treating $500 as Interest Expense is sufficient.  For business accounting, it involves making the $500 a contra-liability and amortizing it as interest expense over the course of life of the loan. I would take each of these items and any others and consider how you would count it as an expense in the other direction. If you have an account for parking expenses or general transportation funds, credit that account for a refund on your parking. If you have an account for expenses on technology purchases, you would credit that account if you sell a piece of equipment as you replace it with an upgrade. If you lost money (perhaps in a jacket) how would you account for the cash that is lost? Whatever account would would subtract from put a credit for cash found. IRS Publication 502: Medical expenses are the costs of diagnosis, cure, mitigation, treatment, or prevention of disease, and the costs for   treatments affecting any part or function of the body. Loan interest and fees do not meet this definition.  Your loan interest and fees are a cost of the payment method you chose (a loan), not a cost of medical treatment. The IRS makes clear where loan interest is deductible.  Publication 936 discusses home mortgage interest deductions, and Publication 970 specifically discusses student loan interest deductions. Considering Publication 502's definition of a medical expense, combined with the absence of a publication discussing medical expense loan interest deductions, one must conclude that medical loan interest and fees are not deductible. "Lachlan has $600 cash and a car worth $500. That's $1,100. The new car is priced at $21,800. Lachlan needs a loan for $20,700. However, the finance company insists that the buyer must pay a 10% deposit, which is $2,180. Lachlan only has $1,100, so no loan.  The car dealer wants to make a sale, so suggests some tricks. The car dealer could buy Lachlan's old banger for $1,500 instead of $500, and sell the new car for $22,800 instead of $21,800. Doesn't make a difference to the dealer, he gets the same amount of cash. Now Lachlan has $600 cash and $1,500 for his car or $2,100 in total. He needs 10% of $22,800 as deposit which is $2,280. That's not quite there but you see how the principle works. Lachlan is about $200 short. So the dealer adds $1,200 to both car prices. Lachlan has $600 cash and a car ""worth"" $1,700, total $2,300. The new car is sold for $23,000 requiring a $2,300 deposit which works out exactly.  How could we have found the right amount without guessing?  Lachlan had $1,100. The new car costs $21,800. The dealer increases both prices by x dollars. Lachlan has now $1,100 + x deposit. The car now costs $21,800 + x. The deposit should be 10%, so $1,100 + x = 10% of ($21,800 + x) = $2,180 + 0.1 x.  $1,100 + x = $2,180 + 0.1 x : Subtract $1,100 x = $1,080 + 0.1 x : Subtract 0.1 x 0.9 x = $1,080 : Divide by 0.9 x = $1,080 / 0.9 = $1,200 The dealer inflates the cost of the new car and the value of the old car by $1,200. Now that's the theory. In practice I don't know how the finance company feels about this, and if they would be happy if they found out." So hopefully you are not spending the money before you make it.  If you are, you are asking for trouble.  If not the solution is easy. If you use a spreadsheet for tracking have a item in your checking account running total that is simply CC to pay.   Lets say you just got paid, and your balance is like this: You can then do virtual withdrawals for each category In this case you have 70 left to spend.  Whoops the car gets a flat which costs you 5 that you put on the card and you also pay your rent by CC.  Then your spreadsheet should look like this: You still have the 70 left to spend, and when the CC bill comes due you are free to write the check. This will not result in any finance charges: I wouldn't recommend cutting it quite so close, but as long as you pay the full balance as shown on each statement by the due date shown on that same statement, you won't incur a finance charge. Of course this only applies in the case of ordinary purchases that have a grace period. Thanks for that, it did help.   I think my issue is I don't work in finance itself, I'm a lawyer, and 'capital' generally has a very specific meaning in English company law, where it refers exclusively to shareholder capital.   I realise capital in finance terms includes both debt and equity investment. So if someone would invest 14000 credits on 1st April 2016, he'd get monthly dividend = ((14000 ÷ 14) × 0.0451) × (1 - 1.42 ÷ 100) = 44.459 credits, right? One would get ((14000 ÷ 14) × 0.0451) = 45.1 is what you would get. The expenses are not to be factored. Generally if a scheme has less expense ratio, the yield is more. i.e. this has already got factored in 0.0451. If the expense ratio was less, this would have been 0.05 if expense ration would have been more it would have been 0.040. Can I then consider the bank deposit earning a higher income per month than the mutual fund scheme? As the MIP as classified as Hybrid funds as they invest around 30% in equities, there is no tax on the income. More so if there is a lock-in of 3 years. In Bank FD, there would be tax applicable as per tax brackets. The best way is to retain the charge slips. After you are done for the month you can discard them.   Alternatively if you are using any of the personal finance tool or a simple XLS to track exepnses, it would be easy to figure out what you actually spent and what was not yours. You first compute your Ordinary Income (which includes Dividends, since they are taxed as OI), then you apply the standard tax bracket function to it, which is a piecewise linear function f() such that TAX = f(INCOME). It can be found at About.com. You can transform this into NET_INCOME = g(INCOME) = INCOME - TAX = INCOME - f(INCOME). Presumably g() is what you want to graph. I've actually graphed it before:  Not too interesting, even on a LogLog scale. More interesting is the marginal tax rate, which is the derivative of f(), or the negative of the derivative of g():  ST (straight tax) shows what the marginal tax rate would look like if f() was just f(x)=kx or f(x)=kx+c, i.e. a straight/flat tax. The net tax rate (f(x)/x) actually gets more interesting if you also include [federal subsidies/deductions](Src: http://fbheron.org/wp-content/uploads/2014/03/fedassistance_ft.jpg) as a negative tax:  Capital Gains are taxed separately and have (almost) nothing to do with this function. Corporate tax is not payed by you (although the burden of the tax [technical term] may fall upon you). Sorry I couldn't simplify; taxes are just complicated.