In Warsaw, it is always best to use the services of radio taxi because these are the most reliable and because the operators usually speak English. This is also true in Lódz. The standard charge is about zl 5 to zl 7 for the first kilometer ( 1/2 mi) and zl 1.30 to zl 2 for each kilometer thereafter (about 50% more at night and during holidays). You do not need to tip taxi drivers, although you can round up the fare to the nearest zloty. Avoid unmarked Mercedes cabs as well as taxis that do not have a number and a name of a company you know on the top. Those "independent" taxis are likely to charge far more than the going rate.
Halo Taxi (022/96-23). MPT (022/91-91). OK! Taxi (022/96-28). Partner Taxi (022/96-69). Sawa Taxi (022/644-44-44). Super Taxi (022/96-22). Tele Taxi (022/96-27). Top Taxi (022/96-64). Taxi Wawa (022/96-44).
Taxi Dwa Dwa (042/96-22). Euro Taxi (042/96-67). Merc Taxi (042/650-50-50). Taxi Nova (042/96-24).