* BZ WBK, Poland's third largest bank, posts profit fall in Q1
* BZ WBK's net profit at 453 mln zloty, better than forecast
* Structure of result won't spark share price rise (Adds more details, comment and background)
By Marcin Goclowski
WARSAW, April 26 (Reuters) - Polish lender Bank Zachodni WBK , part of Spain's Banco Santander, reported an almost 19-percent annual fall in its first-quarter net profit due to higher costs and lower revenues.
"The trade result was weaker, and the bank did not receive a dividend from companies from Aviva group as it happened a year ago, also the bank tax rose year-on-year," said Michal Konarski, an analyst with Dom Maklerski mBanku.
Poland's third-largest bank in terms of assets said on Wednesday that its net profit fell to 453 million zloty ($117.39 million) in the first quarter, above analysts' expectations of 441 million zloty.
BZ WBK' net interest income rose 11.5 percent, slightly less than expected, while its fee and commission result was largely flat on the year, as expected.
Konarski said that the results were not attractive enough to spark a share price rise.
BZ WBK stock has risen by almost one fifth so far this year, outperforming the broader banking sector index, after the ruling Law and Justice (PiS) party's decision to abandon its plan to force banks to convert Swiss franc denominated credit portfolios into zlotys at their expense.
BZ WBK is the second major Polish bank reporting results after BCP's Millennium released better than expected profit on Tuesday, lifting expectations that other lenders may also surprise investors.
($1 = 3.8588 zlotys)
Reporting by Marcin Goclowski; Editing by Louise Heavens