DO I NEED VISA AFTER OVERSTAY IN U.S?

im canadian overstayed in U.S for 7 months on 2005 as a tourist(never worked),i was unaware for how long i could stay as we are exempt for visa or any documentation showing the period of stay (I 94)

i left voluntarely(never caught),,,now i heard if you overstay more than 6 months of your period allowed for canadians(180 days) you will be barred for 3 years,now that has been more than 3 years without going back to U.S,will they ask me for visa when i i'll try to visit again?

Technically under the caselaw Canadians cannot receive a ban for merely overstaying in B-2 visitor status. This is what the courts have ruled, however USCIS sometimes do give people bans.

However I wouldn't worry about it, as the US has only just last month started to attempt keeping departure information on Canadian visitors, and it won't be fully in place until 2014, IIRC. In other words, they have no clue when you left unless you tell them.

Is it the same if you started out on a TN visa and then switched to visitor status?

There is no "switch to visitor" status from TN. If your TN runs out or you get terminated from your job, you have to leave the country.

You can switch from TN-1 to B-2, it is possible, but if you've already been in the US on TN-1 for six months in the current calendar year there's a good chance they will deny it.

Steve, could you please elaborate on the caselaw you are referring to when you say that Canadians cannot be barred due to merely an overstay? I and very concerned with that very issue....
Many thanks in advance.

It's from a case involving a guy from Québec, he fought the ban and the immigration court ruled in his favour, IIRC he was given a ban at Derby Line. I'm sure if you talk to someone from AILA they're familiar with it.

CBP and USCIS use a formula for calculating the length of the ban based on the amount of time you overstayed, the court ruled that calculation cannot be used in relation to Canadian visitors, which effectively means they can't be banned merely for overstaying as a visitor, provided they didn't violate their status in some other way, e.g. by working.

They can still deny you from entry for a previous overstay though if the inspecting officer thinks that means you don't have non-immigrant intent, so it's a bit of a grey area because if you're repeatedly denied entry then it's effectively the same as a ban anyway.

In addition, they still ban Canadian citizens, people have been on here who have been banned for overstaying in B-2, but there is caselaw that can be used to challenge the ban.

if you can afford to hire the lawyer to fight it in court.

In addition, they still ban Canadian citizens, people have been on here who have been banned for overstaying in B-2, but there is caselaw that can be used to challenge the ban.

So, am i guessing right that an overstay of about 7 months after H1B expiration would be treated differently, or no? My whole ignorance was that I presumed that H1B rolls into visitors status after expiration. In this case no other violations took place... (i.e no work out of status, or anything at all)
Thanks a lot for your wisdom!

Unfortunately, ignorance is not usually a valid reason for them to overlook an overstay.