You walk past a homeless person and you have a few options — ignore someone obviously in need or try to help: hand them a sandwich or candy bar, a dollar or two.

But there is another way to help. If you think a homeless person needs assistance, you can call 311.

Earlier this year, Mayor Bill de Blasio revamped that system as part of the creation of Home-Stat, his much-touted overhaul of the city’s homeless outreach programs.

Through Home-Stat, city canvassers walk the streets of Manhattan daily in search of homeless individuals and call in the professionals — contracted non-profit outreach workers who find the homeless “clients” and help them out. And the public’s 311 calls serve the same purpose, helping to direct the pros where they need to be.

It’s been six months since the beginning of Home-Stat, and the weather is turning cold — the most dangerous time for those who are homeless. So what happens after the 311 calls and requests? Unfortunately, not much.

Tracking an intractable problem

The data available, 311 calls coded as “Homeless Person Assistance,” show the most common result from both public and canvasser requests is a dead end: the response team couldn’t find the individual in 63 percent of the casesfrom when Home-Stat became operational in April up until October 4.

Twenty-one percent of the time, the response team found the individual and offered services, but he or she refused them.

That means that in 84 percent of 31,105 encounters in six months there was no meaningful outcome.

In just 7 percent of interactions, services were offered and accepted — the city provided anything from transportation to a bed to information and encouragement to a case manager who could help with benefits and mental health assistance, according to the Department of Homeless Services.

Two percent of cases were referred by DHS to the NYPD. The remaining percentage were data errors or happened even less frequently.

What’s a city agency to do?

DHS and others who work with homeless individuals are quick to point out that it often takes more than one conversation to convince someone living on the street to accept help.

You meet them “where they are,” says Giselle Routhier, policy director at the Coalition for the Homeless. If they want “a blanket to stay warm, that’s what you give.” Then you come back next week. Many conversations down the line, they might agree to come indoors.

Most of all, says Routhier, you have to offer what those who are homeless want. That’s housing.

De Blasio knows this, and is attempting to build more housing, with some focus on supportive housing units — rooms that come bundled with social services, a proven strategy for keeping the formerly homeless housed.

The announcement of Home-Stat earlier this year was supposed to be a bold new way to grapple with street homelessness. He had been responding to a homelessness crisis that critics said was becoming increasingly visible.

But besides a commitment to keeping better data, Home-Stat’s major innovation is the canvassers, who count and call in issues but do not actually interact with the homeless. Often, their labor results in outreach teams left scratching their heads when they can’t find their targets.

Perhaps, over time, limited interactions will change a homeless person’s mind. But maybe some of the resources used on the search could be devoted to improving the services, or something else that would make each contact more effective — and make the promise of each 311 call more real.