Do You Think Stamps Form The 1980-S Till 2013 Will Increase In Price?

Thanks all :)

"Numbers-wise, yes, these covers will be rare."

Not even a little. Think of all the dealers, ebay sellers, and collectors that use discount postage. I alone send 20 - 50 covers out per week using old postage, and I'm just a gnat among ebay sellers.

A used stamp properly posted in its time period will always be as valuable if not more valuable than a used stamp off cover.

Where their first lesson will be: "You've been collecting something of no interest or value to other collectors."

Cheers,

/s/ ikeyPikey (who is commenting on the irony, and does the same thing)

The old saying a picture is worth a thousand words - going out in the mail today.

I thought postage due stamps ($5 in upper right corner) were invalid for postage.

N400
So consider this... what makes any US stamp have value? The answer is simple: scarcity. The problem you face here is literally 100's of millions or even over 1 billion of these stamps are produced. Now, Errors, Freaks, Oddities among them CAN and DO have value and increase in value, but this will be due to some significant differentiation from the 100's of millions of others. And in that case, keep them mint. For instance, even in the "modern" era of stamps, errors like the 1610c ($1 inverted) has a value of $17,500, or with a color omitted like the 1610a or 1610b, with a CV of $200). But their common variety brethren 1610 unused is $2 or used is 25c. This is a stamp from 1979. And as of today, is 40 years old. It took 40 years to essentially double in value, but good luck finding someone willing to pay the $2 for the $1 stamp.
Modern stamps that DO have good value tend to be the high value stamps for all the same reasons that some of the most valued stamps from the early years are so valuable, like a Scott 39. Imagine paying $33 for a stamp today, as that was the value of 90c in 1860, and then NOT using that stamp. Most people when buying that postage expect to use it. And most people who get a used postage will just throw away the envelope. There are MUCH fewer $20 stamps sold than 42c stamps. So the high value stamps ($5+ since around 1940) do retain some value. But the garden variety everyday letter work-horse derivative stamps (and even "commemorates") are essentially valueless. I have volumes of them that come from collections I buy that I can't even give away.
So the short answer to your question is:
Look for errors, freaks and oddities, keep those. The rest... use them as postage. That's the best value you can get from them aside from the enjoyment of just looking at their marvelous design.

You forgot demand.

"I thought postage due stamps ($5 in upper right corner) were invalid for postage."
I wondered about that myself and checked with the PO before using. The only thing I have that I cannot use are non-profit and official. Even the precancels are OK according to my local PO.

I don't see that anyone asked the OP if these are US stamps; if so then I agree they are probably best used for postage. There may be some exceptions such as the Priority Mail high values but anything else, I wouldn't be holding onto them.

wheelman, your PO is incorrect. Postage due stamps are NOT valid for postage. Precancels take a permit.

Your local P.O. is incorrect. Coincidentally enough, just yesterday I was reading an article in an issue of [i]The American Stamp Dealer & Collector[i] by Wayne Youngblood (or Randy Neil...don't recall) where he specifically mentioned Dues not being valid for postage, along with Special Delivery and Certified Mail stamps, along with a few others.

The reason for this is that these stamps pay for an additional service and weren't issued to pay for postage.

What we have here is the makings of a 'Postage Due due to Postage Due' situation...

Newby Stamper: "They may increase if you keep them for a couple hundred years. (Maybe.)"

Reminds me of a joke from the 1960s ... An astronaut gets lost in space and when he returns its 100 years later. The first thing he does is find a pay phone (yep, sure) and calls is brokerage to see how his investments are doing. 'Welcome back sir, your account is worth 10 Billion dollars.' Wow, the astronaut thinks, I'm rich. At that point the phone operator breaks in and says 'Please deposit $1M for another 5 minutes.'

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Here's a Xmas Miracle: a half-way legible shpritzy pictorial slogan cancel on a GPU (Genuinely Postally Used) cover.

Maybe, someday, someone will be collecting shpritzy pictorial slogan cancels - one for each regional processing center, or one for each holiday, or any postmarked on their birthday ... and I'll get ... what? ... five bucks?

Whatever I get, I'll bet it pays better than hoarding denominated mint postage.

Cheers,

/s/ ikeyPikey (who, yes, kept the entire)