README

This Laravel package allows you to calculate personal income tax according to Thai regulations.

Installation

Tested on Laravel 8 but should be working on any version of Laravel.

composer require anurat/laravel-thai-tax

After installed, it can be used through ThaiTax facade.

use ThaiTax;

Usage

The simplest use of the library is to provide netIncome() (THB)
then call incomeTax()

ThaiTax::netIncome(500000)->incomeTax();
// 9500 THB

Net income is total incomes minus total expenses minus total deductions.
It is then used to calculate income tax according to personal income tax rate
e.g. https://www.rd.go.th/59670.html

Thai year

You can also provide Thai year to calculate different income tax on different year as follow.

If Thai year is not provided, the current year is used.

ThaiTax::thaiYear(2542)
    ->netIncome(500000)
    ->incomeTax();
// 42500 THB

The earliest year it can calculate is 2542

Incomes and Deductions

Net income can be calculated by using incomes and deductions,
so incomes and deductions can be provided instead of net income.

netIncome() and (all types or incomes and deductions) should not be used together, as they will override each other.

Income

income(float $income) can be used for general type of incomes

ThaiTax::thaiYear(2564)
    ->income(250000)
    ->income(50000)
    ->income(15000)
    ->incomeTax();
// 250 THB    

Also you can use more specific type of incomes
e.g. salary(float $salaryPerMonth) or bonus(float $bonus).

ThaiTax::thaiYear(2564)
    ->income(100000)
    ->salary(50000)
    ->bonus(50000)
    ->incomeTax();
// 41000 THB    

salary() takes monthly salary as an argument so 50,000 will be 600,000 per year.

income(array $incomes) can also accept an array as an argument.

ThaiTax::thaiYear(2564)
    ->income([
        50000,
        50000,
        'salary' => 50000,
        'bonus' => 50000
    ])
    ->incomeTax();
// 41000 THB    

Deduction

For general type of deductions deduction() can be used.

ThaiTax::thaiYear(2564)
    ->income(500000)
    ->deduction(100000)
    ->incomeTax();
// 4500 THB    

Other deduction types are as follow.
It has the benefit of checking for specific rules for that type
e.g. home loan interest may not exceed 100,000 Baht,
it will automatically reduce to 100,000 Baht if more is provided.

spouse(bool $hasSpouse) // คู่สมรส

children(int $noOfChildren) // บุตร

parents(int $noOfParents) // บิดามารดา

disabiltites(int $noOfDisabilities) // ผู้พิการ/ทุพพลภาพ

childBirth(float $cost) // ฝากครรภ์และทำคลอด

insurancePremium(float $premium) // ประกันชีวิต

annuityInsurancePremium(float $premium) // ประกันชีวิตแบบบำนาญ

homeLoanInterest(float $interest) // ดอกเบี้ยซื้อที่อยู่อาศัย

providentFund(float $fund) // กองทุนสำรองเลี้ยงชีพ

socialSecurity(float $security) // ประกันสังคม

donation(float $donation) // บริจาค

educationDonation(float $donation) // บริจาคเพื่อการศึกษา/กีฬา

politicalParty(float $donation) // บริจาคพรรคการเมือง

shopDeeMeeKeun(float $shop) // ช๊อปดีมีคืน

ThaiTax::thaiYear(2564)
    ->income(1000000)
    ->spouse(true)
    ->children(2)
    ->parents(3)
    ->insurancePremium(50000)
    ->incomeTax();
// 39500 THB    

deduction() can also accept an array as an argument.

ThaiTax::thaiYear(2564)
    ->income(1000000)
    ->deduction([
        'spouse' => true,
        'children' => 2,
        'parents' => 3,
        'insurancePremium' => 50000
    ])
    ->incomeTax();
// 39500 THB