* BBVA 9-month results before market open
* Net profit seen down 45 percent
* Mexico in focus outside of Spain
MADRID, Oct 31 Spain's second-biggest bank BBVA will report a 45 percent decline in nine-month net profit on We dnesday, a Reuters poll forecasts, as it writes off more losses on bad real estate investments.
Profit margins at Spanish banks are waning as they belatedly recognise the effects of a decade-long housing boom that crashed in 2008, leading the government to ask for a 100 billion euro ($129 billion) credit line from Europe to bail out the weakest lenders.
BBVA, along with rival Santander, easily passed an independent stress test in September that showed the bank would have a capital surplus in an extreme economic downturn.
The lender has made less than half of the writedowns against soured real estate assets demanded by the government to clean up banks' balance sheets and get credit flowing once more to families and businesses in a worsening recession.
A poll of eight analysts estimated BBVA would report net profit of 1.7 billion euros, down 45 percent, on net interest income of 11.2 billion euros, up 15 percent on the year ago period.
Outside of Spain, focus will center on Mexico, which has replaced Brazil as the investors' darling of Latin America thanks to its thriving economy and a growing middle class that is just starting to open bank accounts and take out loans.
Mexico accounts for around 11 percent of profits at the bank, compared to Spain's contribution of around 36 percent.
For a BBVA earnings poll, please click on ($1 = 0.7749 euros) (Reporting By Sonya Dowsett; Editing by Hans-Juergen Peters)