Huzurabad had recorded 84.5 per cent polling in 2018 elections while the turnout was 76.37 per cent in Badvel.
Barring minor incidents, the polling was peaceful in both the constituencies.
Election Commission officials said the final polling figures may slightly vary as those standing in queues at 7 p.m. were allowed to cast their votes.
Counting of votes will be taken up on November 2.
Telangana Chief Electoral Officer Shashank Goel said the polling percentage has gone up compared to 2018 elections. He expressed satisfaction over the conduct of polls in a smooth and peaceful manner.
Noting various parties have lodged complaints against each other, he said they were looking into the complaints of irregularities and will take appropriate action after receiving reports from poll observers.
The polling began at 7 a.m. at all 306 polling centres in Huzurabad and the process was peaceful, barring minor incidents of clashes between workers of ruling Telangana Rashtra Samithi (TRS) and opposition Bharatiya Janata Party (BJP).
District Election Officer and Karimnagar District Collector R.V. Karnan, who visited a few polling stations to oversee the polling process, said Electronic Voting Machines (EVMs) at a couple of places developed snags but they were immediately replaced.
Long queues of voters were seen at the polling centres since morning. A total of 2,37,036 voters are eligible to cast their votes in the byelection.
Authorities conducted the polling process in compliance with Covid-19 protocol. At every polling station, voters were allowed in after thermal screening. The officials also made markings on ground to ensure social distancing.
Twenty companies of central forces in addition to the personnel from State police were deployed as part of the elaborate security arrangements.
A total of 30 candidates are in fray in the by-election, caused by the resignation of Eatala Rajender after he was dropped from state cabinet. Rajender also quit the TRS to join the BJP.
Rajender, who had been representing Huzurabad seat since 2009, is locked in a three-cornered contest with Gellu Srinivas Yadav of the TRS and B. Venkat Narsing Rao of the Congress.
In Badvel, the voter turnout was less compared to the 2018 elections. State Chief Electoral Officer K. Vijayanand said the polling was peaceful.
The poll authorities had made elaborate security arrangements for the polling in the constituency in Kadapa, home district of Chief Minister Y.S. Jagan Mohan Reddy.
Badvel, reserved for Scheduled Castes, is one of the Assembly segments of Kadapa Lok Sabha seat being held by the YSR family for over three decades.
Vijayanand monitored the polling process through webcasting.
A total 2,16,139 voters including 1,07,340 women and two transgenders were eligible to cast their votes.
Fifteen companies of the Central Reserve Police Force (CRPF), the Central Industrial Security Force (CISF) and the Border Security Force (BSF) and 1,606 personnel of Andhra Pradesh Police were deployed.
A total of 15 candidates tested their political fortunes in the bypoll, caused by the death of sitting MLA G. Venkatasubbaiah of the ruling YSR Congress Party (YSRCP).
The YSRCP has fielded his wife Dasari Sudha, who is locked in a three-cornered contest against Congress' M. Kamalamma and BJP's P. Suresh.
Main opposition Telugu Desam Party (TDP) is not contesting the byelection in line with its tradition of supporting the family members of the deceased MLA.