74Smash
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Smash Score👍 Solid Smash
Denver's walk-up smashburger legend since 1980 - Westword's clear pick over rival Jim's Burger Haven. Thin, seared hard, under $10.
Representative photography restored from the prior published page. Actual appearance may vary.
Grandpa's Burger Haven has been a fixture of Southwest Denver's Federal Boulevard corridor since 1980, when it split off from Jim's Burger Haven - itself a Denver institution dating to 1961. The two restaurants have been sparring across Denver's collective memory ever since, drawing loyal partisans who will tell you at length why their side of the family split is the right one. In October 2024, new owners took over with an explicit commitment to preserving what made Grandpa's worth arguing about in the first place.
The Steak Burger is the whole menu in one item: a thin smashed patty, seared hard on a flat-top, American cheese, mustard, pickles, and onions on a sesame bun. No frills, no customization theater. Westword ran the definitive side-by-side with Jim's in November 2025 and declared Grandpa's the clear champion on burger flavor - 'the one that elicited a yum after every bite.' The large is the correct order at $9.49 - one of Denver's best-value smashburgers from any era.
Grandpa's is the clear Burger Haven champion based solely on burger flavor. It's the one that elicited a 'yum' after every bite.
Grandpa's is a better experience all around, IMHO. Better pickles, better IQF fries and they take the time to get it right.
#2 in Denver - praised for the huge double-patty burger and overall value, history, and size novelty.
Grandpa's Burger Haven (#6): A walk-up window on Federal that's been slinging smashburgers since before the trend. No seating, no gimmicks, just a really good burger.
Grandpa's Burger Haven has been doing this since long before smashburgers were a trend - the results are dependable if not revelatory. Worth a trip to Federal Boulevard for the experience alone.
4.4 stars from over 2,400 Google reviews. Consistent praise across years of reviews - regulars cite decades of loyalty and note the new owners have maintained the original recipe and style.
I've been going since 1987 and the new owners kept everything that matters. Still the best cheap burger in Denver - order the large, always the large.