First-Class Mail Letter (Stamped)
First-Class Mail Letter (Metered)
Postcard
First-Class Mail Large Envelope (Flat)
Estimated 2018 Postage Cost
$0.00
Understanding the 2018 Postage Rate Increase
On January 21, 2018, the United States Postal Service (USPS) implemented new postage rates for domestic and international mailing services. This calculator helps you determine the historical cost of mailing letters and flats based on the 2018 pricing structure. Understanding these rates is crucial for auditing past mailing expenses or understanding historical pricing trends.
Key Changes in 2018
The most notable change in 2018 was the increase of the First-Class Mail Forever stamp price from $0.49 to $0.50. This one-cent increase affected millions of households and businesses. While the base rate increased, the cost for each additional ounce remained steady.
Mail Class
2017 Rate
2018 Rate (Effective Jan 21)
First-Class Letter (1 oz)
$0.49
$0.50
First-Class Metered Letter (1 oz)
$0.46
$0.47
Domestic Postcard
$0.34
$0.35
First-Class Flat (1 oz)
$0.98
$1.00
Each Additional Ounce
$0.21
$0.21
How Weights Are Calculated
Under the 2018 guidelines, postage is rounded up to the nearest ounce. For example, a letter weighing 1.2 ounces is charged at the 2-ounce rate. This applies to both standard letters and large envelopes (flats).
Weight Limits for 2018 First-Class Mail
Letters: Maximum weight of 3.5 ounces. Items over 3.5 ounces are typically charged as Large Envelopes (Flats).
Large Envelopes (Flats): Maximum weight of 13 ounces. Items exceeding 13 ounces generally upgrade to Priority Mail.
Postcards: Must meet specific rectangular dimensions.
Why Use a Historical Rate Calculator?
While current postage rates differ from those in 2018, a historical calculator is valuable for:
Accounting Audits: Verifying expenses from the 2018 fiscal year.
Comparative Analysis: Comparing logistics costs over time to track inflation and operational overhead.
Legal Documentation: Confirming the cost of service at a specific point in time for legal disputes.
function calculatePostage2018() {
// Clear previous results and errors
var errorDiv = document.getElementById("error-msg");
var resultArea = document.getElementById("result-area");
var finalCostDisplay = document.getElementById("finalCost");
var breakdownDisplay = document.getElementById("breakdown");
errorDiv.style.display = "none";
resultArea.style.display = "none";
// Get Inputs
var mailType = document.getElementById("mailType").value;
var weightRaw = document.getElementById("weightOz").value;
var weight = parseFloat(weightRaw);
// Validation
if (isNaN(weight) || weight 1) {
// Usually postcards over a certain thickness or weight become letters,
// but for this specific 2018 calculator, we will just warn.
breakdownText = "Note: Standard postcards typically do not exceed 1 oz. ";
}
// Check if weight exceeds class limit
if (weight > selectedRate.max) {
errorDiv.innerHTML = "Weight exceeds the limit for " + selectedRate.name + " (" + selectedRate.max + " oz).In 2018, this item would likely be classified as a different mail class (e.g., Priority Mail or Flat).";
errorDiv.style.display = "block";
return;
}
// Calculation Logic:
// 1st oz is base price.
// Additional ounces (rounded up) cost 'add' price.
var roundedWeight = Math.ceil(weight);
var additionalOunces = 0;
if (roundedWeight > 1) {
additionalOunces = roundedWeight – 1;
}
if (mailType === "postcard") {
// Postcards are flat rate
totalCost = selectedRate.base;
breakdownText += "Flat rate for postcard.";
} else {
totalCost = selectedRate.base + (additionalOunces * selectedRate.add);
breakdownText += "Base Rate (1 oz): $" + selectedRate.base.toFixed(2);
if (additionalOunces > 0) {
breakdownText += "+ " + additionalOunces + " additional oz @ $" + selectedRate.add.toFixed(2) + "/oz";
}
}
// Update UI
finalCostDisplay.innerHTML = "$" + totalCost.toFixed(2);
breakdownDisplay.innerHTML = "Class: " + selectedRate.name + "" +
"Billed Weight: " + roundedWeight + " oz" +
breakdownText;
resultArea.style.display = "block";
}