Everyone knows New York City taxes are high, but that’s not the only problem: They’re also complicated, confusing and unfair — especially property taxes.

Which is why Assemblywoman Nicole Malliotakis (R-SI) just rolled out a plan to overhaul Gotham’s property-tax system. And why a newly formed panel is holding hearings to come up with fixes.

It’s also why a tax-reform group is suing the state and city (a judge just gave the suit the go-ahead). And why the Citizens Budget Commission — which has documented property-tax inequities for years — put out another report on them just last month.

How complex is it? The city divides property into four tax “classes”: small homes, apartments, utilities and commercial and industrial real estate. Each class is taxed based on different rules, rates and possible exemptions. Thus, each class winds up with a different average “effective tax rate” (i.e., a property’s tax bill as a percentage of its market value).

A 2016 CBC report notes that small homes are hit with the lowest ETRs, 0.74 percent. Small rental buildings average more than twice that, and larger ones five times the rate.

Tenants feel the pain when landlords fold their tax bills into the monthly rent: If the rent is too damn high, it’s in large part because the tax is too damn high.

Meanwhile, commercial property-tax rates are even higher, hurting job providers.

Single-family homes do OK compared to elsewhere in the region and even the nation. But as a Lincoln Institute study found some years back, the effective rate for a 20-unit rental building here is twice the national average for a big city. And ETRs on commercial property run 76 percent above the US big-city average.

Equally troubling: Within classes, rates vary widely. ETRs for small homes run from nearly zero to as much as 1.2 percent, the CBC report said. “A single-family home worth $500,000, for example, could see a tax bill anywhere from less than $100 to $6,000,” it observed.

One key factor: Hikes in assessments are capped, so they phase in slowly. Yet caps help those who least need it: homeowners whose property values are rising fast, such as those in gentrifying neighborhoods.

Point is, it’s all a big mess. And property taxes only add to the crunch of all the other taxes: on businesses, incomes, sales . . .

Clearly, reforms are in order — not just to lower taxes but to simplify them and make them fairer. Yet, for all the renewed interest in doing that, don’t expect much to change.

For one thing, the city’s spending growth means City Hall can’t afford to cut tax rates. And any attempt to level the playing field will create armies of winners and losers; what New York pol is willing to risk the political consequences?

No, sad to say, New Yorkers will be stuck with crazy property taxes until their leaders find the courage to upset the apple cart by finally taming the city budget.