90 day extension

The DPF will only allow an extension (Prorrogação de Prazo de Estada) that falls within the 180 day per year limit. The calculation is done automatically so you'd only get a 45 day extension when you apply anyway.

Cheers,
James     Expat-blog Experts Team

thanks whats going to be the best idea
  how about i go to argentina for 45 days
  would brazil allow me back in to fly home to uk?
  thanks
    will the pf ask questions relating to my return ticket which is beyond 180 days?
if i say i will leave for say argentina will they want to see a ticket for proof?
thanks again

Yes, they're really going to be very concerned about a return ticket more than 180 days from entry. I've heard conflicting reports from members that when you pop out of Brazil to one of the surrounding countries for a visit during a Visa Waiver Program stay whether or not the clock keeps running on your stay in Brazil's calculation or not too, so you'd have to confirm that beforehand as well.

I know in the USA for example, you are on a VWP and pop over to Canada or Mexico those days are still counted against your stay in the USA. I really think it's just the same here.