Oahu residents will see their electrical bills dip slightly this month while customers in Maui County and on Hawaii island are facing continued sharp increases due to higher fuel costs.

Hawaiian Electric Co. said last week that the typical HECO bill in November for an Oahu household using 500 kilowatt-hours is $139.52, or 25.9 cents a kilowatt-hour, down 39 cents from $139.91 in October when it was also 25.9 cents a kilowatt-hour due to rounding.

But while Oahu customers will receive a little financial relief, residential customers on Hawaii island, Maui island, Lanai and Molokai will have to dig a little deeper to make their payments after seeing their bills increase by as much as 18 percent over the past two months.

Maui Electric Co. customers will see their bills spike in November for the second straight month. The average bill for a Maui household using 500 kilowatt-hours is $158.18, or 29.7 cents a kilowatt-hour. That was up $10.54 from $147.64, or 27.6 cents a kilowatt-hour, in October. Over the last two months, MECO customers have seen their average bill jump $19.94, or 14 percent, from $138.24 in September.

MECO customers on Molokai using 400 kilowatt-­hours of electricity will pay an average of $153.07, or 35.8 cents a kilowatt-hour, compared with $136.35, or 31.7 cents a kilowatt-hour, in October. Molokai customers have seen their bills soar $23.08, or 18 percent, from $129.99 in September.

Lanai residents using 400 kilowatt-hours of electricity will pay an average of $153.90, or 36.1 cents a kilowatt-hour, compared with $146.72, or 34.3 cents a kilowatt-hour, in October. Lanai customers have seen their bill jump $8.46, or 6 percent, from $145.44 in September.

Bills on Lanai and Molokai are calculated based on a typical household using 400 kilowatt-hours of electricity in a month. This is due to lower energy use compared with Maui, Hawaii island and Oahu, HECO said.

HECO, MECO and Hawaii Electric Light Co. monthly bills include the cost for kilowatt-­hours used, in addition to other charges.

The average cost in November for HELCO residential customers using 500 kilowatt-hours is $177.60, or 33.2 cents a kilowatt-hour, up $4.63 from $172.97, or 32.3 cents a kilowatt-­hour, in October. Over the past two months, HELCO customers have seen their bills rise $6.08, or 3.5 percent, from $171.52 in September.

“Crude oil is up about $10 a barrel from a year ago and since June we’ve seen an uptick in fuel prices,” HECO spokeswoman Shannon Tangonan said.

Fuel prices dictate electrical bills, as HECO’s energy mix is primarily made up of oil. In 2016, HECO’s energy mix was roughly 67.9 percent oil on Oahu. HECO imports oil primarily from Southeast Asia and the Middle East. The remainder of the energy comes from coal, 21.4 percent; solid waste, 6 percent; wind, 3.4 percent; solar, 0.8 percent; and biofuel, 0.5 percent.

The Kauai Island Utility Cooperative’s effective rate increased to 33.36 cents a kilowatt-­hour in November, up from 32.67 cents a kilowatt-­hour in October. The typical bill for a household using 500 kilowatt-­hours in November is $177.39, including a $10.58 customer base charge. In October the bill was $173.92.

The cost of electricity in the state is more than double the national average, as Hawaii residents paid an average of 28.76 cents a kilowatt-­hour for electricity in August. The national average was 13.19 cents in the same month, according to the latest figures from the U.S. Energy Information Administration.