Poll taxes had been enacted in eleven Southern states after Reconstruction as a measure to prevent poor black people from voting. At the time of this amendment's passage, only five states still retained a poll tax.
The full text of this amendment follows:
The right of citizens of the United States to vote in any primary or other election for President or Vice President, for electors for President or Vice President, or for Senator or Representative in Congress, shall not be denied or abridged by the United States or any State by reason of failure to pay poll tax or other tax.
United States Constitution