Short answer
Islam fixes some dues itself, such as zakat on Muslims, ushr on crops, kharaj on land and jizya on non-Muslim citizens. Beyond these, a government may levy fair taxes for real public needs, and paying them is required. Unjust taxes are condemned. Paying tax does not replace zakat.
Zakat is fard and has fixed rates and recipients. A just government may impose further levies for genuine public needs (called nawa'ib by Hanafi jurists), and citizens must pay lawful taxes. Taking people's wealth by unjust taxation (maks) is a major sin for the one who imposes it.
The four schools agree on this.
Explanation
The classical Islamic state had several revenues, each with its own rules:
- Zakat: 2.5% of savings and trade goods above the nisab, and set rates on livestock, paid by Muslims to eight named groups (9:60).
- Ushr: a tenth (or a twentieth on irrigated land) of crops from certain land.
- Kharaj: a land tax on conquered farmland, fixed in Umar's time.
- Jizya: a yearly sum from able-bodied non-Muslim men in place of military service and zakat. See What is jizya?
- Customs: Umar set duties on traders crossing the borders.
Can a ruler take more than this? Hanafi jurists discuss levies imposed for things like guarding a city, digging canals or paying soldiers when the treasury cannot cover them, and they treat fair levies of this kind as a real debt on the people. Scholars of the other schools, such as al-Shatibi among the Malikis, reached a similar view for times of need. The condition is justice: the money must go to public benefit and be taken fairly.
Unjust taxation is something else. The Prophet ﷺ said of a woman whose repentance was complete that if a sahib maks (an unjust tax collector) had repented like her, he would have been forgiven, showing how grave that sin is. The sin is on those who impose and collect unjust taxes, not on the ordinary citizen who pays.
For Muslims in the US, UK or elsewhere, paying the taxes the law requires is part of keeping your agreement with the country. See Do Muslims have to pay taxes? Tax is never counted as zakat: see Can tax count as zakat?
The evidence
Quran, Surah At-Tawba 9:103
خُذْ مِنْ أَمْوَٰلِهِمْ صَدَقَةًۭ تُطَهِّرُهُمْ وَتُزَكِّيهِم بِهَا وَصَلِّ عَلَيْهِمْ ۖ إِنَّ صَلَوٰتَكَ سَكَنٌۭ لَّهُمْ ۗ وَٱللَّهُ سَمِيعٌ عَلِيمٌ ﴿١٠٣﴾
Take, [O, Muhammad], from their wealth a charity by which you purify them and cause them increase, and invoke [Allah 's blessings] upon them. Indeed, your invocations are reassurance for them. And Allah is Hearing and Knowing.
Zakat is the duty Allah Himself set on Muslims' wealth.
Quran, Surah Al-Hashr 59:7
مَّآ أَفَآءَ ٱللَّهُ عَلَىٰ رَسُولِهِۦ مِنْ أَهْلِ ٱلْقُرَىٰ فَلِلَّهِ وَلِلرَّسُولِ وَلِذِى ٱلْقُرْبَىٰ وَٱلْيَتَٰمَىٰ وَٱلْمَسَٰكِينِ وَٱبْنِ ٱلسَّبِيلِ كَىْ لَا يَكُونَ دُولَةًۢ بَيْنَ ٱلْأَغْنِيَآءِ مِنكُمْ ۚ وَمَآ ءَاتَىٰكُمُ ٱلرَّسُولُ فَخُذُوهُ وَمَا نَهَىٰكُمْ عَنْهُ فَٱنتَهُوا۟ ۚ وَٱتَّقُوا۟ ٱللَّهَ ۖ إِنَّ ٱللَّهَ شَدِيدُ ٱلْعِقَابِ ﴿٧﴾
And what Allah restored to His Messenger from the people of the towns - it is for Allah and for the Messenger and for [his] near relatives and orphans and the [stranded] traveler - so that it will not be a perpetual distribution among the rich from among you. And whatever the Messenger has given you - take; and what he has forbidden you - refrain from. And fear Allah; indeed, Allah is severe in penalty.
Public revenue in Islam serves the whole community, not a few.
Sahih Muslim 1695
Sahih... لقد تابت توبة لو تابها صاحب مكس لغفر له ...
"She has repented with a repentance that, if an unjust tax collector repented like it, he would be forgiven."
Unjust taxation is among the gravest sins.
Where the ruling is recorded
- al-Hidaya, Kitab al-Siyar, chapter on ushr and kharaj. Rules of land taxes and their recipients.
- Radd al-Muhtar (Ibn Abidin), Kitab al-Kafala, discussion of nawa'ib. Levies imposed by the ruler for public needs and when they are a just debt.
- Kitab al-Kharaj (Imam Abu Yusuf), Sections on kharaj, jizya and customs. The early Hanafi treatise on state revenue written for the caliph.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.