We'd like to remind Forumites to please avoid political debate on the Forum... Read More »
We're aware that some users are experiencing technical issues which the team are working to resolve. See the Community Noticeboard for more info. Thank you for your patience.
📨 Have you signed up to the Forum's new Email Digest yet? Get a selection of trending threads sent straight to your inbox daily, weekly or monthly!
help with "rule of 78" loan calculation?
Options
Comments
-
The "Logic" which lies behind the Rule Of 78 Interest rebate formula is as follows.
Suppose a loan last for 10 years i.e. 120 months.
Then there is an assumption that you repay the capital at the rate of one unit per month.
So
The interest in month 1 is based on 120 units of capital
The interest in month 2 is based on 119 units of capital
The interest in month 3 is based on 118 units of capital
The interest in month 4 is based on 117 units of capital
.
.
.
.
etc
.
.
.
The interest in month n is based on (121-n) units of capital.
.
.
.
The interest in month 118 is based on 3 units of capital
The interest in month 119 is based on 2 units of capital
The interest in month 120 is based on 1 unit of capital.
The Rule of 78 lets you off all the interest that would have been due, using this model, after you stopped paying.
So initially you are going to pay interest on
120 +119 +118+n 117 +116 ...... +5 +4 +3 +2 +1
units of capital
This happens to add up to (120*119)/2
If you have m months left then the interest you get let off is on
m + (m-1) + (m-2) + (m-3) + ..... + 3 +2 +1 units of capital
Which happens to add up to m*(m-1)/2
So the fraction of the total interest you are rebated is
m*(m-1)/2
(120*119/2
or
m*(m-1)
120*119
And if the loan is for n months then the fraction of Interest rebated is
m*(m-1)
n*(n-1)
The amount of Interest rebated is
I *m*(m-1)
n*(n-1)
The Consumer Credit Act allows the lender to add a further two months to the period for which payments have been made when calculating the rebate.
The effect of this is that it reduces the value of m used in the above formula by 2 which makes the amount of the rebate lower.
N.B. For a one year loan
The number of months is 12
The number of units of interest charged is
12 +11 +10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1 = 78
Hey presto The Rule Of 78................................I have put my clock back....... Kcolc ym0 -
Very interesting Robert.
Excellent post.Mortgage Feb 2001 - £129,000
Mortgage July 2007 - £0
Original Mortgage Termination Date - Nov 2018
Mortgage Interest saved - £63790.60
ISA Profit since Jan 1st 2015 - 98.2% (updated 1 Dec 2020)0 -
Thank You MLC...............................I have put my clock back....... Kcolc ym0
-
Hi,
I am looking for advice or confirmation that my redemption figure is correct.
Don't really understand the formulas above and would appreciate if anyone could help.
I took out a loan and these are the details -
LOAN DETAILS
Loan = £15,000 over 60 months.
APR = 10.2%
Interest = £4,322.40
Total Amount Payable = £19,322.40
Monthly Instalment = £322.04
INSURANCE DETAILS (Payment Protection)
Insurance Amount = £3,223.03
Interest = £928.37
Total Amount Payable = 4151.40
APR = 10.2%
Total Amount Repayable (Loan + Insurance) = £23,473.80
Monthly Payment = £391.23 x 60 Months.
We have paid 6 payments = £2,347.38
Today we got our settlement figure = £15,594.37
Our first monthly payment started 3 months after we had received the money, the three months are not included in the 60 month repayment plan as I have the dates of first and last payment.
It just seems a lot of money to settle a loan. I don't understand how I can pay over £2,300 back and still owe them an extra £590 plus the amount originally borrowed. Thats nearly £3,000 for borrowing £15,000 for less than a year.
I would really appreciate some help on this because I feel as if I've been mugged.
Regards
Pefki0 -
I am sorry but I have no reason to think that the settlement figure is too high.
A major factor in your current situation is that you signed up to pay 60 monthly payments and only paid 6.
You signed up to pay£23,473.80 but only paid £2347.77
N.B. This is not Finanancial or Legal Advice................................I have put my clock back....... Kcolc ym0 -
I am sorry but I have no reason to think that the settlement figure is too high.
A major factor in your current situation is that you signed up to pay 60 monthly payments and only paid 6.
You signed up to pay£23,473.80 but only paid £2347.77
N.B. This is not Finanancial or Legal Advice.0 -
What I don't understand is how can they continue to charge you interest on the money you have borrowed when you have given it back.
You actually borrowed £15,000 + £3223.03
i.e.
£18223.03
You then repaid
£2347.38
Leaving
£15875.65
The settlement figure is
£15,594.37
It looks, at first sight, as if the loan company have had a bad time too.
They have not even got back the money they have loaned to you.
They have in fact let you off the interest for all but about the first six months. i.e. They do not go on charging you interest after the loan has been settled.
This is what they do in accordance with the rule of 78.
So if you are hard done by and the loan company is hard done by what is the explanation.
It may well be that when you were charged £3223.03 insurance the loan company got some substantial commission.
Do you know if your insurance is quite independent of the loan and continues for a five year period since the premium was all paid on day one................................I have put my clock back....... Kcolc ym0 -
What is the easiest method to find out if a loan uses Rule 78 for early redemption or not?0
-
The answer may be in the T&C's, but it's probably best to call the loan company up and ask them directly.Mortgage Feb 2001 - £129,000
Mortgage July 2007 - £0
Original Mortgage Termination Date - Nov 2018
Mortgage Interest saved - £63790.60
ISA Profit since Jan 1st 2015 - 98.2% (updated 1 Dec 2020)0 -
Hi
I understand rule of 78 over 1 year, if over 2 years is it the same principle, each month is assigned a number (month 1 being 24, month 2 being 23 back to 1. All these totalled = 300 therefore over 2 years the first months interest equals 24/300's of the total?0
This discussion has been closed.
Confirm your email address to Create Threads and Reply

Categories
- All Categories
- 350.9K Banking & Borrowing
- 253.1K Reduce Debt & Boost Income
- 453.5K Spending & Discounts
- 243.9K Work, Benefits & Business
- 598.7K Mortgages, Homes & Bills
- 176.9K Life & Family
- 257.2K Travel & Transport
- 1.5M Hobbies & Leisure
- 16.1K Discuss & Feedback
- 37.6K Read-Only Boards