ACTmapi property boundaries. What the map shows, and what it doesn't. A guide from Surveyor Canberra. You have opened ACTmapi, found your block and seen a neat line around it. Now you want to use that line: for a new fence, a carport close to the side boundary, a retaining wall, or to check what a neighbour is saying. The short answer is that ACTmapi tells you which block is yours and what applies to it. It is not the record of where the boundary sits on the ground. That record is the deposited plan, and the marks a registered surveyor places from it. This is general information only, not legal advice. Does ACTmapi show your exact boundary? No, and it does not claim to. The ACT Government describes ACTmapi's material as a general reference source, and asks users to check its accuracy and get professional advice before relying on it in any important matter. The Territory's own description of its block data adds that block boundaries may not always align exactly, and that the legal definition of a block is defined in the deposited plan. So the map line is a good picture of your block. The deposited plan is the definition. Marks placed by a registered surveyor put that definition on the ground. ACTmapi is the right place to start. The ACT Government points owners to the ACTmapi Basic Map to find their block and section numbers, the zoning of the block, and the types of development allowed, with the development controls themselves in the Territory Plan. For those questions, the map is enough, and you do not need a survey. The trouble starts when a line on screen is used as a measurement. A fencer setting posts, a builder setting out a slab near a side boundary, or an owner pacing out a retaining wall, all need the boundary's exact position on the ground. Development controls in the Territory Plan apply to your block, and working out where new work sits against them starts with knowing where the boundary is. And the ACT Government warns that if you build over or too close to utility assets, you can be liable to remove the obstruction or pay to move the mains. An old fence is not a better guide. It may have been built to the line, or near it, decades ago. Two records decide where your boundary is: the deposited plan, and the survey marks. When a block is registered, it appears on a deposited plan registered with the Land Titles Office, and the legal definition of the block is in that plan. Deposited plans are among the plans surveyors use as the origin of the marks used to redefine a boundary. You can buy the plan yourself through ACTLIS, the ACT Land Information System. A plan search needs the plan number. If you do not have it, start with a title search by street address: it gives you the plan number and a link to the plan. At 1 July 2026, Access Canberra lists a certificate of title search at $36, a deposited plan search at $26, a Crown lease search at $36, and an instrument or dealing search at $24. The plan is a set of measurements. Marks placed by a registered surveyor are those measurements on the ground. The ACT Government is plain about it: you can't survey a boundary yourself. Only surveyors can do this for you, as long as they're registered under the Surveyors Act 2007. A boundary survey shows where the legal boundaries of your block sit on the ground, and how nearby fences or buildings relate to them. The surveyor gathers the registered plans and older records, works out where the boundaries should fall, finds and measures existing survey marks on site, and, where your quote includes marking, marks the boundary so you can fence or build to it. You receive a plan of the boundary and nearby structures, or a survey certificate for a development application. One rule matters once marks are in. Disturbing a survey mark is an offence under section 53 of the Surveyors Act, except where it is removed to put up a fence or do construction work on or near the boundary, or there is another reasonable excuse. If a peg is in the way of something else, ask the surveyor before moving it. We work across Canberra and the ACT, with over nine years' experience. For free advice and an estimate, call (02) 5114 2569, or send your address and what you are planning through the contact form. The fee table, the official ACTLIS video and every source are in the written guide.