No further calculation or adjustment is required when the total share is 1 (or 100%). However, this situation may not often exist in the real world, so the fixed shares (i.e., Dhawoo al-Furudh) do not remain constant and either increase or decrease through redistribution. Under Islamic inheritance calculations, four possible scenarios may exist; Kamil (i.e., complete), Radd (i.e., Return, Redistribution, Reversion or Decrease), Awal or Awwal or Aul (i.e., Increase), and Tasib (i.e., Residuary) if AsAbah (i.e., Residuary sharer) survives. All these scenarios can be solved using numerical expression or the LCM (i.e., Least common multiple) methods of computations. In the Kamil scenario, no further calculation is required because the total share is one (i.e., 100%). In Radd doctrine, all the shares are increased proportionally except the spouse shares (however, it allows this in some countries). In Awwal doctrine, all the shares are reduced proportionally. The Residuary scenario exists when an eligible residuary survives, and the inheritance share is left to distribute. Even though it is relatively simple to learn, you cannot get full confidence until you practice the problems and different scenario examples. Wassiyyah's Islamic Inheritance course allows practicing your learning through examples using the Mathematics Algebraic expression and LCM (Least common multiple) methods. The Dhawoo ar-Rahim (i.e., distant kindred) eligibility and computations of shares (al-Fard) are outside the scope of this blog. Other possible situations may exist that cannot fit in these scenarios, for example, Al-Himariyyah, Al-Kdariyyah, Al-Mushtarika, etc., However, these scenarios are unique, and their calculation has a fixed methodology based on Sunni Islamic ruling. These special scenarios do not fall under normal calculations and have been vastly discussed by Islamic scholars, attorneys, and lawyers.
Before we learn about Calculations
It would be best you refer to "7 FUNDAMENTALS OF ISLAMIC INHERITANCE LAW" for dynamic and simultaneous application for calculating Islamic inheritance shares. The dynamicity of application is more applicable to this article than any other. You should be well versed and have a good understanding of all the following items, and that's why Islamic inheritance law is deemed a complex subject to learn.
Prescribed, Residuary and Distant kindred shares
Conditions and Eligibility
Exclusion or Hajb rules
Madhab's differences of opinions
Kamil, Radd and Awal principles
Islamic Inheritance Calculations
We will demonstrate rules and the principles of calculating Islamic Inheritance as per Sunni Islamic jurisprudence. Your journey of Islamic Inheritance shares calculations will be more straightforward once you have a good understanding of these four examples.
Calculation of Islamic Inheritance shares
After getting familiarity with Islamic Inheritance rules, you are almost ready to learn about calculation methodology. We will take three cases, Kamil, Radd, and Awal, where most of the inheritor's situations would match. It may not cover some special situations, but we assure you that you will get a reasonably good idea after learning this methodology after learning. For Steps 1 and 2, watch the Video "Islamic Inheritance shares - Learn in 10 min" under the Youtube channel "Wassiyyah" to learn quickly about Islamic Inheritance shares.
Case 1: Kamil (i.e., Perfect)
When the total share is equal to "ONE" then there is no further calculation required and distribute the inheritance as per the calculation.
For example, if Husband and Wife both left with Father, Maternal Grandmother (i.e. Mother of Mother), Single Daughter and Single Daughter of Son. Calculate Total share as per steps below.
Total share = 1/6 (for Father) + 1/6 (for Maternal Grandmother) + 1/2 (for Single Daughter) + 1/6 (for Single Daughter of Son) = 1
Total share is ONE and all shares distributed perfectly without requiring any further calculation (i.e. Kamil or Perfect case).
Apply all shares to assets after deducting debts, taxes, expenses, Zakat, Kaffarat and Bequest (as per Islamic Will or Trust).
Case 2: Awal or Awwal or Aul shares (i.e., Share increased proportionally)
When the total share is greater than "ONE" and irrespective of residuary alive or not, every share needs reduce proportionally to make it "ONE."
For example, Husband left with Wife, Paternal Grandfather (i.e. Father of Father), Paternal Grandmother (i.e. Mother of Father), Maternal Grandmother (i.e. Mother of Mother) and Multiple daughters. Calculate Total share as per steps below.
Total share = 1/8 (for Wife) + 1/6 (for Paternal Grandfather) + 1/12 (for Paternal Grandfather) + 1/12 (for Paternal Grandmother) + 2/3 (for Multiple daughters) = 9/8
Total share is 9/8 i.e. More than ONE. So all shares needs to be reduced to make the Total share to be ONE.
Use Awal share formulae (in above table) and calculation will give Total share = 1/9 + 4/27 + 2/27 + 2/27 + 16/27 = 1 i.e. ONE that is desired.
Apply all shares to assets after deducting debts, taxes, expenses, Zakat, Kaffarat and Bequest (as per Islamic Will or Trust).
Case 3: Radd share (i.e., Share decreased proportionally)
When a Total share is less than 1 (i.e., ONE) and no residuary is alive, every share needs to increase proportionally to make the Total share equal to"ONE." You should know the following three things before you apply Radd.
Radd applies to all prescribed sharers except Spouse as per all Fiqh or Madhab (i.e., Islamic jurisprudence school). However, some world countries such as Egypt and India, where legal laws have chosen to include the Spouse's share, need to increase by applying Radd irrespective of Madhab's opinions.
Radd is allowed as per Hanafi and Hanbali but is not allowed as per Shafii and Maliki Fiqh (i.e., Madhab).
Radd is not applicable if any Residuaries are alive.
For example (Hanafi and Hanbali), Husband left with Wife, Mother and Single daughter. Calculate Total share as per steps below.
Total share = 1/8 (for Wife) + 1/6 (for Mother) + 1/2 (for Single daughter) = 19/24
Total share is 19/24 i.e. Less than ONE. So all shares (except Wife's share, However, as we mentioned above some of world countries do allow Radd for Spouse) needs to be increased to make the Total share to be ONE.
Use Radd share formulae (in above table) and calculation will give Total share = 1/8 + 7/32 + 21/32 = 1 i.e. ONE that is desired.
Apply all shares to assets after deducting debts, taxes, expenses, Zakat, Kaffarat and Bequest (as per Islamic Will or Trust).
For example (Shafii and Maliki), Husband left with Wife, Mother and Single daughter. Calculate Total share as per steps below.
Total share = 1/8 (for Wife) + 1/6 (for Mother) + 1/2 (for Single daughter) = 19/24
Total share is 19/24 i.e. Less than ONE. The Residue = 1 - 19/24 = 5/24. The Residue "5/24" will go to Bat-Ul-Mal. In non-Muslim majority countries, the Residue will go to Muslim government registered organization.
Calculation will give Total share = 1/8 + 1/6 + 1/2 + 5/24 = 1 i.e. ONE that is desired.
Apply all shares (except Residue) to assets after deducting debts, taxes, expenses, Zakat, Kaffarat and Bequest (as per Islamic Will or Trust).
Case 4: Residuary share
When a Total share is less than 1 (i.e., ONE) and if residuary is alive, the Residue = 1 - Total share will be distributed to Residuary.
For example, Wife left with Husband, Father, Mother, Son and Daughter. Calculate Total share as per steps below.
Total share = 1/4 (for Husband) + 1/6 (for Father) + 1/6 (for Mother) = 7/12.
Total share is 7/12 i.e. Less than ONE. Calculate Residue = 1-7/12 = 5/12.
In this case, Residuary (Son and Daughter as in this case presence of Son convert Daughter to be Residuary) are available. So the Residue "5/12" will be distributed among Son and Daughter in 2: 1 (Male gets the double the share of Females).
Use Residuary male share and Residuary female share formulae (in above table) and calculation will give Total share = 1/4 + 1/6 + 1/6 + 5/36 + 5/18 = 1 i.e. ONE that is desired.
Apply all shares to assets after deducting debts, taxes, expenses, Zakat, Kaffarat and Bequest (as per Islamic Will or Trust).
Radd vs. Residuary case
You should make a note for two things between Radd and Residuary case.
Radd case is only possible if Total Share is less than ONE and Residuary is not alive. If Residuary is alive then, Residue = 1 - Total share will be distributed to Residuary.
If any inheritors are eligible to receive Residue, it must not consider as a Prescribed share. For example, Daughters have prescribed shares, but if Sons are alive, Daughters will not be regarded as Prescribed sharers in the calculations for Residue. The formula for Residue = 1- Total share where Total share equals the sum of "Eligible prescribed shares."
Allah, the Most Glorified and the Most High, knows the best. As a human, We are limited to everything and can not perceive it in totality...