If you wish to change your electricity, gas, water, internet and cables to your name, you must call each company to change your name and then close the account when you move.
In Korea, utility bills will be issued one month after moving in. When you move out, call each company and tell them the number of the meter for the gas and electricity and you may pay by making the bank deposit or pay the landlord before leaving.

Internet & Cable company in Korea
1. KT Olleh - www.olleh.com Tel - 100 without area code (toll- free)
                                                  mobile phone - with the area code + 100 -
                                                  #2  English Consultation

2. SK Broadband - www.skbroadband.com  Tel - 103 (without area code )
3. LG U+ - www.uplus.co.kr Tel- 101 (without area code )
4. Yongsan cable