A method for generating a physical layer, PHY, data unit for transmission via a communication channel, the method comprising: providing a first set of modulation coding schemes, MCSs, that correspond to a first channel bandwidth, wherein the first set of MCSs excludes MCSs that do not satisfy a padding-related constraint; providing a second set of MCSs that correspond to a second channel bandwidth, wherein the second set of MCSs excludes MCSs that do not satisfy the padding-related constraint and wherein providing the second set of MCSs includes excluding MCSs from the first set of MCSs that do not satisfy the padding-related constraint, wherein a subset of one or more MCSs in the first set of MCSs satisfies the padding-related constraint with respect to the first channel bandwidth, but the subset of one or more MCSs does not satisfy the padding-related constraint with respect to the second channel bandwidth, and wherein the padding-related constraint corresponds to mod N CBPS N ES D R = 0, wherein N CBPS is a number of encoded bits per OFDM symbol, wherein N ES is a number of FEC encoders being utilized for encoding the information bits, wherein D R is 2 for a code rate of 1 2, wherein D R is 3 for a code rate of 2 3,, wherein D R is 4 for a code rate of 3 4, and wherein D R is 6 for a code rate of 5 6; selecting an MCS from the first set of MCSs when the PHY data unit is to be transmitted using a channel having the first channel bandwidth; selecting an MCS from the second set of MCSs when the PHY data unit is to be transmitted using a channel having the second channel bandwidth; adding padding bits to the information bits to generate payload information; encoding the payload information according to the selected MCS; modulating the encoded payload information according to the selected MCS; and forming a plurality of Orthogonal Frequency Division Multiplexing, OFDM, symbols based on the modulated encoded payload information. providing a first set of modulation coding schemes, MCSs, that correspond to a first channel bandwidth, wherein the first set of MCSs excludes MCSs that do not satisfy a padding-related constraint; providing a second set of MCSs that correspond to a second channel bandwidth, wherein the second set of MCSs excludes MCSs that do not satisfy the padding-related constraint and wherein providing the second set of MCSs includes excluding MCSs from the first set of MCSs that do not satisfy the padding-related constraint, wherein a subset of one or more MCSs in the first set of MCSs satisfies the padding-related constraint with respect to the first channel bandwidth, but the subset of one or more MCSs does not satisfy the padding-related constraint with respect to the second channel bandwidth, and wherein the padding-related constraint corresponds to mod N CBPS N ES D R = 0, wherein N CBPS is a number of encoded bits per OFDM symbol, wherein N ES is a number of FEC encoders being utilized for encoding the information bits, wherein D R is 2 for a code rate of 1 2, wherein D R is 3 for a code rate of 2 3,, wherein D R is 4 for a code rate of 3 4, and wherein D R is 6 for a code rate of 5 6; selecting an MCS from the first set of MCSs when the PHY data unit is to be transmitted using a channel having the first channel bandwidth; selecting an MCS from the second set of MCSs when the PHY data unit is to be transmitted using a channel having the second channel bandwidth; adding padding bits to the information bits to generate payload information; encoding the payload information according to the selected MCS; modulating the encoded payload information according to the selected MCS; and forming a plurality of Orthogonal Frequency Division Multiplexing, OFDM, symbols based on the modulated encoded payload information.