The Union-Tribune has a greater one-day reach than any other medium in the San Diego region, with daily readership in excess of 860,000 and more than 1 million readers on Sunday (not including online readership). In fact, an ad that appears in the Sunday edition of the Union-Tribune and SignOnSanDiego.com reaches 1,363,361 San Diego adults (or 61 percent of all adults in San Diego County).

Today's Local News is a free daily newspaper delivered Tuesday through Sunday to non-subscribers in key North County ZIP codes. This provides merchants with affordable, expanded distribution in this important area, while offering readers award-winning local news coverage.

The San Diego Union Tribune is in the San Diego, CA DMA. The San Diego Union Tribune offers ROP and insert advertising opportunities in its daily and Sunday circulation. This paper also offers total market coverage (TMC) through a non-subscriber distribution. Echo Media has direct relationships with over 7,500 newspapers providing tremendous local coverage.

The San Diego Union-Tribune uses their TMC package, The U-TMC, to reach households that do not subscribe to the newspaper. Advertisers can increase their coverage of the San Diego market by having their offer delivered by US Mail every Friday and Saturday. Loose circulars and inserts are packaged together as a direct mail product that serves the end need of local and national advertisers. The wrap is also inserted into the San Diego Union-Tribune on Thursdays, so on-page advertisers reach both subscribers and non-subscribers.

As of 2013, the Union Tribune includes the former Escondido Northern Times Californian.