The latest disclosure of MPs' expenses show those around the Whanganui area all spent less on travel and accommodation than they did last quarter.
Whanganui MP Chester Borrows spent $19,904 in the January to March quarter, compared to $22,936 in the previous one.
Meanwhile, Te Tai Hauauru MP Adrian Rurawhe was down to $18,810 compared to $23,295 the previous quarter.
Rangitikei MP Ian McKelvie spent $13,925, down from $17,882.
Mr Borrows was the sixth highest-spending National MP, which he attributed mainly to travel.
"I do a lot of driving of myself around the electorate and I claim mileage on my car, so most of my expenses will be mileage," he said.
"The reason I've spent more will be because I frequently drive around my electorate, a lot more than other MPs do.
"I drive myself to work quite often, as opposed to being driven at the taxpayers' expense."
Mr Borrows said he was entitled to be driven by a BMW limousine, which would make the expenses "much higher", but he chose to drive himself.
Mr Rurawhe was the eighth-highest spender for Labour, which he attributed to the size of his electorate.
He said the size of the electorate stretched from Porirua to Tirau. "I've got the largest electorate in the North Island."
Much of his expenses went on travel to different areas of the electorate, and the other contributor was accommodation.
Mr Rurawhe said he would often have to "stay away from home" when doing electorate work.
"It just really depends what I'm doing," he said.
Sometimes it would not be safe to drive a long distance home after working a 10 to 12-hour day, he said.
"I appreciate that we have these services available. If we didn't, I wouldn't be able to service my electorate."
Nationally, MPs spent $1.4 million in the January to March quarter, a slight increase on last year.
The minister with the biggest bill was Trade Minister Todd McClay, who spent $108,774, mostly on international travel - though some of that total was carried over from the previous quarter.
The biggest-spending MP, excluding ministers, was leader of the opposition Andrew Little, who spent $36,009 in the last quarter.
That was partly due to international travel from the previous quarter, including a trip to the United States to meet trade delegates.
He was followed by Labour MP Kelvin Davis, who lives in the Far North and represents the large Te Tai Tokerau electorate, and National list MP Nuk Korako.
On average, Labour MPs spent $15,444 each, New Zealand First MPs spent $14,652, Green MPs spent $14,509, Maori Party MPs spent $12,234 and National MPs (excluding ministerial expenses) spent $8505.